Introduction

This Rmarkdown script contains the full results supporting the main paper (but very little interpretation). As described in detail in the README.md document, this script uses various types of input data (linguistic and genetic) and multiple methods of analysis.

Data

Tone

The data sources

WALS

WALS uses a categorical classification with 3 ordered categories ‘None’ < ‘Simple’ < ‘Complex.’ There are 513 languages with data.

None Simple Complex
301 127 85
***Figure 1.*** _Distribution of tone in WALS._

Figure 1. Distribution of tone in WALS.

LAPSyD

LAPSyD gives both a categorical classification with 5 ordered categories ‘None’ < ‘Simple’ < ‘Complex,’ and the actual count of tones. There are 569 languages with data.

None Marginal Simple Moderately complex Complex
386 8 94 39 42
***Figure 2.*** _Distribution of tone in LAPSyD._

Figure 2. Distribution of tone in LAPSyD.

***Figure 3.*** _Distribution of tone counts in LAPSyD._

Figure 3. Distribution of tone counts in LAPSyD.

Dediu & Ladd (2007)

This uses a categorical classification with 2 (presence/absence) categories ‘No’ and ‘Yes.’ There are 60 languages with data.

No Yes
30 30
***Figure 4.*** _Distribution of tone in Dediu & Ladd (2007)'s database._

Figure 4. Distribution of tone in Dediu & Ladd (2007)’s database.

PHOIBLE

PHOIBLE gives the actual count in 2030 languages with data.

0 1 2 3 4 5 6 7 8 9 10
1495 4 148 173 101 60 25 11 4 6 3
***Figure 5.*** _Distribution of tone in PHOIBLE._

Figure 5. Distribution of tone in PHOIBLE.

WPHON

WPHON gives the actual count in 3160 languages with data.

0 1 2 3 4 5 6 7 8 9 10 11 12
2193 3 427 222 174 66 43 11 15 2 1 2 1
***Figure 6.*** _Distribution of tone in WPHON_

Figure 6. Distribution of tone in WPHON

Relationships between data sources

WALS - LAPSyD

  • languages with values in at least one classification: 724
  • shared languages: 358
  • language with values only in WALS: 155
  • language with values only in LAPSyD: 211
  None Marginal Simple Moderately complex Complex
None 229 2 1 0 0
Simple 4 4 59 12 4
Complex 1 0 2 16 24
***Figure 7.*** _Relationship between tone in WALS and LAPSyD._

Figure 7. Relationship between tone in WALS and LAPSyD.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
515.4 8 3.407e-106 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
515.4 NA 9.999e-05 * * *

WALS - Dediu & Ladd (2007)

  • languages with values in at least one classification: 550
  • shared languages: 23
  • language with values only in WALS: 490
  • language with values only in Dediu & Ladd (2007): 37
  No Yes
None 12 1
Simple 0 5
Complex 0 5
***Figure 8.*** _Relationship between tone in WALS and Dediu & Ladd (2007)'s database._

Figure 8. Relationship between tone in WALS and Dediu & Ladd (2007)’s database.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
19.3 2 6.44e-05 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
19.3 NA 9.999e-05 * * *

LAPSyD - Dediu & Ladd (2007)

  • languages with values in at least one classification: 609
  • shared languages: 20
  • language with values only in LAPSyD: 549
  • language with values only in Dediu & Ladd (2007): 40
  No Yes
None 12 0
Marginal 0 1
Simple 0 1
Moderately complex 0 2
Complex 0 4
***Figure 9.*** _Relationship between tone in LAPSyD and Dediu & Ladd (2007)'s database._

Figure 9. Relationship between tone in LAPSyD and Dediu & Ladd (2007)’s database.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
20 4 0.0004994 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
20 NA 9.999e-05 * * *

PHOIBLE - WALS

  • languages with values in at least one classification: 2074
  • shared languages: 469
  • language with values only in PHOIBLE: 1561
  • language with values only in WALS: 44
  None Simple Complex
0 272 70 41
1 1 0 0
2 1 17 4
3 2 7 12
4 0 6 6
5 0 4 7
6 1 6 3
7 0 1 2
8 0 0 1
9 0 0 3
10 0 0 2
***Figure 10.*** _Relationship between tone in PHOIBLE and WALS (barplot)._

Figure 10. Relationship between tone in PHOIBLE and WALS (barplot).

***Figure 11.*** _Relationship between tone in PHOIBLE and WALS (boxplots)._

Figure 11. Relationship between tone in PHOIBLE and WALS (boxplots).

Analysis of Variance Model
  Df Sum Sq Mean Sq F value Pr(>F)
wa_tone 2 371.4 185.7 76.53 1.826e-29
Residuals 466 1131 2.427 NA NA
  diff lwr upr p adj
Simple-None 1.225 0.8137 1.637 3.976e-11
Complex-None 2.292 1.829 2.754 1.3e-11
Complex-Simple 1.066 0.5312 1.602 1.099e-05

PHOIBLE - LAPSyD

  • languages with values in at least one classification: 2132
  • shared languages: 467
  • language with values only in PHOIBLE: 1563
  • language with values only in LAPSyD: 102
  None Marginal Simple Moderately complex Complex
0 314 6 57 13 15
1 1 0 0 0 0
2 2 1 13 0 1
3 0 0 3 9 3
4 0 0 2 4 2
5 0 0 1 3 6
6 1 0 1 3 0
7 0 0 1 0 1
8 0 0 0 0 1
9 0 0 0 0 2
10 0 0 0 0 1
***Figure 12.*** _Relationship between tone in PHOIBLE and LAPSyD (barplot)._

Figure 12. Relationship between tone in PHOIBLE and LAPSyD (barplot).

***Figure 13.*** _Relationship between tone in PHOIBLE and LAPSyD (boxplots)._

Figure 13. Relationship between tone in PHOIBLE and LAPSyD (boxplots).

Analysis of Variance Model
  Df Sum Sq Mean Sq F value Pr(>F)
la_tone 4 368.3 92.06 61.43 1.324e-41
Residuals 462 692.3 1.499 NA NA
  diff lwr upr p adj
Marginal-None 0.2511 -1.03 1.532 0.9835
Simple-None 0.7475 0.3239 1.171 1.812e-05
Moderately complex-None 2.34 1.719 2.962 4.919e-12
Complex-None 2.84 2.219 3.462 4.874e-12
Simple-Marginal 0.4963 -0.8264 1.819 0.8425
Moderately complex-Marginal 2.089 0.6904 3.488 0.0004863
Complex-Marginal 2.589 1.19 3.988 5.735e-06
Moderately complex-Simple 1.593 0.8892 2.297 1.263e-08
Complex-Simple 2.093 1.389 2.797 4.965e-12
Complex-Moderately complex 0.5 -0.3381 1.338 0.4765
***Figure 14.*** _Relationship between tone in PHOIBLE and number of tones in LAPSyD (jittered for increased visibility)._

Figure 14. Relationship between tone in PHOIBLE and number of tones in LAPSyD (jittered for increased visibility).

Pearson’s product-moment correlation: la_n_tones and ph_n_tones
Test statistic df P value Alternative hypothesis cor
13.86 465 8.444e-37 * * * two.sided 0.5406
Spearman’s rank correlation rho: la_n_tones and ph_n_tones
Test statistic P value Alternative hypothesis rho
7516233 1.916e-39 * * * two.sided 0.5572

PHOIBLE - Dediu & Ladd (2007)

  • languages with values in at least one classification: 2050
  • shared languages: 40
  • language with values only in PHOIBLE: 1990
  • language with values only in Dediu & Ladd (2007): 20
  No Yes
0 20 7
1 0 0
2 1 3
3 0 3
4 0 2
5 0 3
6 0 0
7 0 0
8 0 1
9 0 0
10 0 0
***Figure 15.*** _Relationship between tone in PHOIBLE and Dediu & Ladd (2007)'s database (barplot)._

Figure 15. Relationship between tone in PHOIBLE and Dediu & Ladd (2007)’s database (barplot).

***Figure 16.*** _Relationship between tone in PHOIBLE and Dediu & Ladd (2007)'s database (boxplots)._

Figure 16. Relationship between tone in PHOIBLE and Dediu & Ladd (2007)’s database (boxplots).

Welch Two Sample t-test: ph_n_tones by dl_tone (continued below)
Test statistic df P value Alternative hypothesis
-4.264 19.13 0.0004133 * * * two.sided
mean in group No mean in group Yes
0.09524 2.421

WPHON - WALS

  • languages with values in at least one classification: 3188
  • shared languages: 485
  • language with values only in WPHON: 2675
  • language with values only in WALS: 28
  None Simple Complex
0 270 9 3
1 0 0 0
2 13 73 9
3 6 24 18
4 1 11 20
5 0 2 10
6 0 1 8
7 0 0 2
8 0 0 3
9 0 0 1
10 0 0 0
11 0 0 0
12 0 0 1
***Figure 17.*** _Relationship between tone in WPHON and WALS (barplot)._

Figure 17. Relationship between tone in WPHON and WALS (barplot).

***Figure 18.*** _Relationship between tone in WPHON and WALS (boxplots)._

Figure 18. Relationship between tone in WPHON and WALS (boxplots).

Analysis of Variance Model
  Df Sum Sq Mean Sq F value Pr(>F)
wa_tone 2 1094 546.8 490 7.358e-117
Residuals 482 537.9 1.116 NA NA
  diff lwr upr p adj
Simple-None 2.151 1.882 2.421 5.838e-11
Complex-None 3.954 3.633 4.276 5.838e-11
Complex-Simple 1.803 1.438 2.169 5.838e-11

WPHON - LAPSyD

  • languages with values in at least one classification: 3211
  • shared languages: 518
  • language with values only in WPHON: 2642
  • language with values only in LAPSyD: 51
  None Marginal Simple Moderately complex Complex
0 334 1 11 2 1
1 0 0 1 0 0
2 19 6 49 6 6
3 3 0 11 20 6
4 2 0 6 6 9
5 0 0 2 1 7
6 0 0 1 0 4
7 0 0 0 0 1
8 0 0 0 0 3
9 0 0 0 0 0
10 0 0 0 0 0
11 0 0 0 0 0
12 0 0 0 0 0
***Figure 19.*** _Relationship between tone in WPHON and LAPSyD (barplot)._

Figure 19. Relationship between tone in WPHON and LAPSyD (barplot).

***Figure 20.*** _Relationship between tone in WPHON and LAPSyD (boxplots)._

Figure 20. Relationship between tone in WPHON and LAPSyD (boxplots).

Analysis of Variance Model
  Df Sum Sq Mean Sq F value Pr(>F)
la_tone 4 868.5 217.1 278.1 6.119e-127
Residuals 513 400.6 0.7808 NA NA
  diff lwr upr p adj
Marginal-None 1.561 0.6375 2.484 4.595e-05
Simple-None 1.97 1.672 2.267 2.014e-10
Moderately complex-None 2.732 2.304 3.16 2.014e-10
Complex-None 4.063 3.645 4.48 2.014e-10
Simple-Marginal 0.4092 -0.5438 1.362 0.7655
Moderately complex-Marginal 1.171 0.1699 2.173 0.01257
Complex-Marginal 2.502 1.505 3.499 3.885e-10
Moderately complex-Simple 0.7623 0.273 1.252 0.0002305
Complex-Simple 2.093 1.613 2.573 2.014e-10
Complex-Moderately complex 1.331 0.7601 1.901 4.023e-09
***Figure 21.*** _Relationship between tone in WPHON and number of tones in LAPSyD (jittered for increased visibility)._

Figure 21. Relationship between tone in WPHON and number of tones in LAPSyD (jittered for increased visibility).

Pearson’s product-moment correlation: la_n_tones and wp_tone
Test statistic df P value Alternative hypothesis cor
31.51 516 2.475e-122 * * * two.sided 0.8112
Spearman’s rank correlation rho: la_n_tones and wp_tone
Test statistic P value Alternative hypothesis rho
3591376 2.359e-142 * * * two.sided 0.845

WPHON - Dediu & Ladd (2007)

  • languages with values in at least one classification: 3176
  • shared languages: 44
  • language with values only in WPHON: 3116
  • language with values only in Dediu & Ladd (2007): 16
  No Yes
0 22 1
1 0 0
2 1 6
3 0 7
4 0 4
5 0 0
6 0 1
7 0 2
8 0 0
9 0 0
10 0 0
11 0 0
12 0 0
***Figure 22.*** _Relationship between tone in WPHON and Dediu & Ladd (2007)'s database (barplot)._

Figure 22. Relationship between tone in WPHON and Dediu & Ladd (2007)’s database (barplot).

***Figure 23.*** _Relationship between tone in WPHON and Dediu & Ladd (2007)'s database (boxplots)._

Figure 23. Relationship between tone in WPHON and Dediu & Ladd (2007)’s database (boxplots).

Welch Two Sample t-test: wp_tone by dl_tone (continued below)
Test statistic df P value Alternative hypothesis
-8.362 22.18 2.64e-08 * * * two.sided
mean in group No mean in group Yes
0.08696 3.286

WPHON - PHOIBLE

  • languages with values in at least one classification: 3760
  • shared languages: 1430
  • language with values only in WPHON: 1730
  • language with values only in PHOIBLE: 600
  0 1 2 3 4 5 6 7 8 9 10
0 918 1 8 6 8 3 1 0 0 0 0
1 3 0 0 0 0 0 0 0 0 0 0
2 131 0 27 21 16 7 2 1 1 0 0
3 48 0 17 37 6 5 6 2 1 0 0
4 43 0 14 4 13 6 7 2 1 0 0
5 9 0 2 5 4 7 1 0 0 1 1
6 5 0 1 4 1 2 2 1 0 1 0
7 3 0 0 1 0 1 1 0 0 0 0
8 2 0 0 0 1 0 0 2 0 2 0
9 0 0 1 0 0 1 0 0 0 0 0
10 0 0 0 0 0 0 0 0 0 0 0
11 0 0 0 0 0 1 0 0 0 0 0
12 0 0 0 1 0 0 0 0 0 0 0
***Figure 24.*** _Relationship between tone in WPHON and PHOIBLE (barplot)._

Figure 24. Relationship between tone in WPHON and PHOIBLE (barplot).

***Figure 25.*** _Relationship between tone in WPHON and PHOIBLE (scatterplot)._

Figure 25. Relationship between tone in WPHON and PHOIBLE (scatterplot).

Pearson’s product-moment correlation: wp_tone and ph_n_tones
Test statistic df P value Alternative hypothesis cor
26.83 1428 9.157e-129 * * * two.sided 0.579
Spearman’s rank correlation rho: wp_tone and ph_n_tones
Test statistic P value Alternative hypothesis rho
1.97e+08 3.554e-138 * * * two.sided 0.5959

Reconciliating the sources

Collapse LAPSyD 4-way

The 5-level coding in LAPSyD is too fine-grained, especially “Marginal” is very rare, and seemingly quite similar with “Simple” (rather than “None”) in its behaviour in the other data sets. On the other hand, “Moderately complex,” while quite similar with “Complex” (but not “Simple”), seems to have an identity of its own. Thus, I collapsed “Marginal” into “Simple,” resulting in a 4-way classification: “None” < “Simple” < “Moderately complex” < “Complex.”

The content of the sources

With this (and as a reminder), the sources contain the following information:

  • LAPSyD:
    • 4-way classification for 569 languages: “None” (386), “Simple” (102), “Moderately complex” (39), “Complex” (42)
    • counts for 569 languages: 0 (386), 1 (6), 2 (89), 3 (47), 4 (22), 5 (6), 6 (8), 7 (3), 9 (1), 11 (1)
  • WALS:
    • 3-way classification for 513 languages: “None” (301), “Simple” (127), “Complex” (85)
  • Dediu & Ladd (2007):
    • binary classification for 60 languages: “No” (30), “Yes” (30)
  • WPHON:
    • counts for 3160 languages: 0 (2193), 1 (3), 2 (427), 3 (222), 4 (174), 5 (66), 6 (43), 7 (11), 8 (15), 9 (2), 10 (1), 11 (2), 12 (1)
  • PHOIBLE:
    • counts for 2030 languages: 0 (1495), 1 (4), 2 (148), 3 (173), 4 (101), 5 (60), 6 (25), 7 (11), 8 (4), 9 (6), 10 (3)

The reconciliation rules

I designed a set of rules for deciding on a set of two “agreement” categorical classifications, based on a precedence of the sources and the patterns of (dis)agreement between them:

  • a binary classification: no tone (“No”) vs any form of tone (“Yes”), and
  • a 3-way classification: “None” < “Simple” < “Complex.”

More precisely, I preferred to use manually-curated categorical classifications to count sources, resulting in the following (rough) ordering: LAPSyD > WALS > Dediu & Ladd (2007) > WPHON > PHOIBLE.

For the sources that give actual numbers (i.e., counts of tones or tone symbols), we observe that 1 is very rare, probably signalling coding errors, marginal systems (“pitch-accent”) or theoretical arguments, so they can probably be safely collapsed it into 2, and then move everything “one step down” (i.e., 2 → 1, 3 → 2, etc) so we have a continuum of counts from 0 onward. With this, the pairwise correlations between the count sources become:

***Figure 26.*** _Relationships between counts after merging 1 into 2 and moving everything down by 1._

Figure 26. Relationships between counts after merging 1 into 2 and moving everything down by 1.

Thus, the main idea is to use LAPSyD wherever these data exists, followed by WPHON and finally PHOIBLE (thus with precedence LAPSyD > WPHON > PHOIBLE). Please note that the counts in WPHON and PHOIBLE are “corrected” to better map on those in LAPSyD and to “predict” missing data, using quadratic regression (i.e., the “corrected” counts are computed as WPHONcorr = 0.079 +0.919WPHON -0.04WPHON2, and PHOIBLEcorr = 0.394 +0.68PHOIBLE -0.037PHOIBLE2, respectively).

The “agreement” classifications

Distributions
Binary classification

# languages with data: 3798:

No Yes
2541 1257
***Figure 27.*** _Distribution of the binary agreement classification of tone._

Figure 27. Distribution of the binary agreement classification of tone.

3-way classification

# languages with data: 3785:

None Simple Complex
2538 936 311
***Figure 28.*** _Distribution of the 3-way agreement classification of tone._

Figure 28. Distribution of the 3-way agreement classification of tone.

Counts

Rounded

# languages with data: 3785:

0 1 2 3 4 5 6 8 10
2544 516 524 114 56 26 3 1 1
***Figure 29.*** _Distribution of the agreement counts of tone._

Figure 29. Distribution of the agreement counts of tone.

Unrounded

# languages with data: 3785:

***Figure 30.*** _Distribution of the agreement counts of tone (unrounded)._

Figure 30. Distribution of the agreement counts of tone (unrounded).

Relationships with original sources
With WALS
Binary classification
  No Yes
None 297 4
Simple 4 123
Complex 0 85
***Figure 31.*** _Relationship between tone in WALS and the agreement binary classification._

Figure 31. Relationship between tone in WALS and the agreement binary classification.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
480.7 2 4.049e-105 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
480.7 NA 9.999e-05 * * *
3-way classification
  None Simple Complex
None 298 3 0
Simple 4 119 4
Complex 1 2 82
***Figure 32.*** _Relationship between tone in WALS and the agreement 3-way classification._

Figure 32. Relationship between tone in WALS and the agreement 3-way classification.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
921 4 4.723e-198 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
921 NA 9.999e-05 * * *
With LAPSyD
Binary classification
  No Yes
None 385 1
Simple 0 102
Moderately complex 0 39
Complex 0 42
***Figure 33.*** _Relationship between tone in LAPSyD and the agreement binary classification._

Figure 33. Relationship between tone in LAPSyD and the agreement binary classification.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
564.4 3 5.148e-122 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
564.4 NA 9.999e-05 * * *
3-way classification
  None Simple Complex
None 386 0 0
Simple 0 102 0
Moderately complex 0 12 27
Complex 0 0 42
***Figure 34.*** _Relationship between tone in LAPSyD and the agreement 3-way classification._

Figure 34. Relationship between tone in LAPSyD and the agreement 3-way classification.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
1028 6 7.755e-219 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
1028 NA 9.999e-05 * * *
Counts

Rounded

***Figure 35.*** _Relationship between tone in LAPSyD and the agreement counts._

Figure 35. Relationship between tone in LAPSyD and the agreement counts.

Pearson’s product-moment correlation: la_n_tones and n_tones
Test statistic df P value Alternative hypothesis cor
Inf 567 0 * * * two.sided 1
Spearman’s rank correlation rho: la_n_tones and n_tones
Test statistic P value Alternative hypothesis rho
0 0 * * * two.sided 1

Unrounded

***Figure 36.*** _Relationship between tone in LAPSyD and the agreement counts (unrounded)._

Figure 36. Relationship between tone in LAPSyD and the agreement counts (unrounded).

Pearson’s product-moment correlation: la_n_tones and n_tones_raw
Test statistic df P value Alternative hypothesis cor
Inf 567 0 * * * two.sided 1
Spearman’s rank correlation rho: la_n_tones and n_tones_raw
Test statistic P value Alternative hypothesis rho
0 0 * * * two.sided 1
With Dediu & Ladd (2007)
Binary classification
  No Yes
No 30 0
Yes 0 30
***Figure 37.*** _Relationship between tone in Dediu & Ladd (2007) and the agreement binary classification._

Figure 37. Relationship between tone in Dediu & Ladd (2007) and the agreement binary classification.

Pearson’s Chi-squared test with Yates’ continuity correction: cooc_tab
Test statistic df P value
56.07 1 7.005e-14 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
60 NA 9.999e-05 * * *
3-way classification
  None Simple Complex
No 24 0 0
Yes 2 8 13
***Figure 38.*** _Relationship between tone in Dediu & Ladd (2007) and the agreement 3-way classification._

Figure 38. Relationship between tone in Dediu & Ladd (2007) and the agreement 3-way classification.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
39.61 2 2.502e-09 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
39.61 NA 9.999e-05 * * *
With PHOIBLE
Counts

Rounded

***Figure 39.*** _Relationship between tone in PHOIBLE and the agreement counts._

Figure 39. Relationship between tone in PHOIBLE and the agreement counts.

Pearson’s product-moment correlation: ph_n_tones and n_tones
Test statistic df P value Alternative hypothesis cor
41.42 2028 2.854e-272 * * * two.sided 0.677
Spearman’s rank correlation rho: ph_n_tones and n_tones
Test statistic P value Alternative hypothesis rho
358843117 0 * * * two.sided 0.7426

Unrounded

***Figure 40.*** _Relationship between tone in PHOIBLE and the agreement counts (unrounded)._

Figure 40. Relationship between tone in PHOIBLE and the agreement counts (unrounded).

Pearson’s product-moment correlation: ph_n_tones and n_tones_raw
Test statistic df P value Alternative hypothesis cor
38.8 2028 9.067e-247 * * * two.sided 0.6527
Spearman’s rank correlation rho: ph_n_tones and n_tones_raw
Test statistic P value Alternative hypothesis rho
488625970 1.276e-243 * * * two.sided 0.6495
With WPHON
Counts

Rounded

***Figure 41.*** _Relationship between tone in WPHON and the agreement counts._

Figure 41. Relationship between tone in WPHON and the agreement counts.

Pearson’s product-moment correlation: wp_tone and n_tones
Test statistic df P value Alternative hypothesis cor
156 3158 0 * * * two.sided 0.9408
Spearman’s rank correlation rho: wp_tone and n_tones
Test statistic P value Alternative hypothesis rho
136411420 0 * * * two.sided 0.9741

Unrounded

***Figure 42.*** _Relationship between tone in WPHON and the agreement counts (unrounded)._

Figure 42. Relationship between tone in WPHON and the agreement counts (unrounded).

Pearson’s product-moment correlation: wp_tone and n_tones_raw
Test statistic df P value Alternative hypothesis cor
168.4 3158 0 * * * two.sided 0.9486
Spearman’s rank correlation rho: wp_tone and n_tones_raw
Test statistic P value Alternative hypothesis rho
689289938 0 * * * two.sided 0.8689

Conclusions about tone

These three agreement tone codings were obtain using the full information from the 5 sources, but, of course, we have information about much fewer languages for this study, so that we end up using fewer languages here.

After this sub-setting, in summary, I used 5 primary sources:

  • WALS: categorical with 3 ordered categories ‘None’ < ‘Simple’ < ‘Complex,’
  • LAPSYD: categorical, recoded with 4 ordered categories ‘None’ < ‘Simple’ < ‘Moderately complex’ < ‘Complex’ by collapsing ‘Marginal’ into ‘Simple,’ and count, from 0 to 10 tones (mean 0.62 and median 0), by collapsing the original 1 tone into the original 2 tones and moving all tones one step down (i.e., original 2 tones become 1 tone),
  • Dediu & Ladd (2007): categorical with 2 (presence/absence) categories ‘No’ and ‘Yes,’
  • WPHON: count, from 0 to 11 tones (mean 0.67 and median 0), by collapsing the original 1 tone into the original 2 tones and moving all tones one step down (i.e., original 2 tones become 1 tone), and
  • PHOIBLE: count, from 0 to 9 tones (mean 0.66 and median 0), by collapsing the original 1 tone into the original 2 tones and moving all tones one step down (i.e., original 2 tones become 1 tone),

From these, I built 3 “agreement” combined and reconciled measures:

  • tone_binary: a binary (presence/absence) variable with categories ‘No’ and ‘Yes,’
  • tone_3way: a categorical variable with 3 ordered categories ‘None’ < ‘Simple’ < ‘Complex,’ and
  • n_tones: count, from 0 to 10 tones (mean 0.61 and median 0).

However, for the analyses reported here, I used the following variables:

  • tone1: this represents directly tone_binary and encapsulates the question “does the language use tone?” contrasting no tone (“No”) versus any type of tone system (“Yes”),
  • tone2: this is the dichotomisation of tone_3way into the question “does the language use a complex tone system?” contrasting complex tone systems (“Yes”) versus no tone and simple tone systems (“No”), and
  • tone counts: this is the n_tones, counting the number of tones/tone symbols in the language.

For counts, I will also use the unrounded (i.e., raw) “counts,” n_tones_raw, varying between 0 to 10 tones (mean 0.67 and median 0.0793991), to avoid any biases induced by numerically rounding to integer counts.

Distribution of retained tone data

Binary

# languages with data: 321:

No Yes
251 70
***Figure 43.*** _Distribution of binary tone._

Figure 43. Distribution of binary tone.

3-way

# languages with data: 314:

None Simple Complex
248 39 27
***Figure 44.*** _Distribution of 3-way tone._

Figure 44. Distribution of 3-way tone.

Counts

# languages with data: 314:

0 1 2 3 4 5 6
249 26 23 6 5 3 2
***Figure 45.*** _Distribution of tone counts._

Figure 45. Distribution of tone counts.

Counts (unrounded)

# languages with data: 314:

***Figure 46.*** _Distribution of tone counts (unrounded)._

Figure 46. Distribution of tone counts (unrounded).

Intersection

There are 314 languages with data for binary, 3-way and counts.

ASPM-D and MCPH1-D population frequencies

I will denote the “derived” alleles of ASPM and MCPH1 (Microcephalin) as ASPM-D and MCPH1-D, respectively.

ASPM-D

ASPM-D this was originally defined in relation to “haplotype 63” and two of its polymorphic nonsynonymous sites in exon 18 in an open reading frame (ORF), A44871G and C45126A with the ancestral alleles, respectively, A and C, and the derived ones, G and A (Mekel-Bobrov et al., 2005, p. 1720). Later relevant publications (Patrick C. M. Wong, Chandrasekaran, & Zheng, 2012; Patrick C. M. Wong et al., 2020) however, use SNP rs41310927 with ancestral allele T and derived allele C. While most databases do contain info about this SNP, others do not, such that I also collected data about SNPs in very tight LD with it: rs41308365, rs3762271, rs41304071, rs147068597 and rs61819087 (the LD data was obtained from LDlink’s “LDproxy Tool” using all populations in that database).

Thus, I collected the following data:

Locus/SNP “derived” allele Datatbases Position and LD to target
“haplotype 63” “haplogroup D” MB2005 the target
rs41310927 C WONG2020, LDLink, gnomAD, dbSNP the target
rs41308365 A LDLink, gnomAD, dbSNP chr1:197070707; D’=1.00, R2=1.00
rs3762271 T LDLink, gnomAD, dbSNP, ALFRED chr1:197070442; D’=1.00, R2=1.00
rs41304071 T LDLink, dbSNP chr1:197063352; D’=1.00, R2=1.00
rs147068597 A LDLink chr1:197058136; D’=1.00, R2=1.00
rs61819087 G LDLink, dbSNP chr1:197084857; D’=1.00, R2=1.00

where the databases are identified as:

Database URL Info ID
Mekel-Bobrov et al. (2005) https://science.sciencemag.org/content/309/5741/1720 The original source; 59 populations MB2005
Patrick C. M. Wong et al. (2020) https://advances.sciencemag.org/content/6/22/eaba5090 Massive experimental study in Cantonese speakers; 1 population WONG2020
LDLink https://ldlink.nci.nih.gov/?tab=home “[…] a suite of web-based applications designed to easily and efficiently interrogate linkage disequilibrium in population groups”; 1000 genomes data in 32 individual and grouped populations LDLink
gnomAD https://gnomad.broadinstitute.org/ Genome Aggregation Database v2.1.1; very broad populations gnomAD
dbSNP https://www.ncbi.nlm.nih.gov/snp/ aggregation of info form multiple databases, mostly using very broad populations dbSNP
1000 genomes https://www.internationalgenome.org/ this info is included in other databases (gnomAD) so is not specifically used here 1KG
ALFRED https://alfred.med.yale.edu/alfred/index.asp The ALlele FREquency Database; lots of info in many populations; unfortunately, for ASPM only one SNP in strong LD with the target rs41310927 (rs3762271) is available ALFRED

All SNPs

I ended up with frequency data about these loci in 170 unique samples coming from 127 unique meta-populations (such as “Han Chinese,” “Italians” or “Finnish”). After making sure the frequencies of these SNPs are very highly correlated (in those samples where they do co-occur), I computed their weighted average frequency (weighed by the number of sampled individuals).

Min. 1st Qu. Median Mean 3rd Qu. Max.
0 0.1012 0.2291 0.2416 0.3886 0.684
***Figure 48.*** _Distribution of the frequency of the "derived" allele of *ASPM* across the world._

Figure 48. Distribution of the frequency of the “derived” allele of ASPM across the world.

Excluding “proxy” SNPs

Of these 7 SNPs, 5 are “proxy” SNPs (rs147068597, rs3762271, rs41304071, rs41308365, rs61819087), representing 289 unique samples (and 233237 total alleles) out of 396 (73%) unique samples (and 367519 total alleles; 63.5%) available for ASPM-D.

Min. 1st Qu. Median Mean 3rd Qu. Max.
0 0.0995 0.2073 0.2275 0.38 0.6
***Figure 50.*** _Distribution of the frequency of the "derived" allele of *ASPM* across the world, excluding the "proxy" SNPs._

Figure 50. Distribution of the frequency of the “derived” allele of ASPM across the world, excluding the “proxy” SNPs.

Due to this high proportion of the data being represented by “proxy” SNPs, I also conducted separate analyses excluding these SNPs.

New samples

Moreover, 111 are new samples from 84 unique (meta)populations, compared to the 59 samples in 56 (meta)populations in the original Mekel-Bobrov et al. (2005). These new samples are distributed as:

Africa Eurasia America Papunesia
12 90 5 4

and the corresponding new (meta)populations as:

Africa Eurasia America Papunesia
12 63 5 4
***Figure 51.*** _Distribution of the "original" and "new" samples of *ASPM*-D across the world._

Figure 51. Distribution of the “original” and “new” samples of ASPM-D across the world.

MCPH1-D

MCPH1-D was originally defined in relation to G37995C in exon 8 in an open reading frame (ORF) with the ancestral allele G, and the derived one C (Evans et al., 2005, p. 1717). Later relevant publications (Patrick C. M. Wong et al., 2020) however, use SNP rs930557 with ancestral allele G and derived allele C. While most databases do contain info about this SNP, others do not, such that I also collected info about the SNP rs1129706 which is in very tight LD with it (the linkage data was obtained from LDlink’s “LDproxy Tool” using all populations in that database).

Thus, I obtained the following data:

Locus/SNP “derived” allele Datatbases Position and LD to target
G37995C C MB2005 the target
rs930557 C WONG2020, LDLink, dbSNP the target
rs1129706 G ALFRED chr8:6304814; D’=0.995, R2=0.936

All SNPs

I ended up with frequency data about these loci in 166 unique samples coming from 128 unique meta-populations. After making sure the frequencies of these SNPs are very highly correlated (in those samples where they do co-occur), I computed their weighted average frequency (weighted by the number of sampled individuals).

Min. 1st Qu. Median Mean 3rd Qu. Max.
0.0315 0.658 0.7986 0.7125 0.8652 1
***Figure 53.*** _Distribution of the frequency of the "derived" allele of *MCPH1* across the world._

Figure 53. Distribution of the frequency of the “derived” allele of MCPH1 across the world.

Excluding “proxy” SNPs

Of these 3 SNPs, 1 are “proxy” SNPs (rs1129706), representing 141 unique samples (and 13028 total alleles) out of 245 (57.6%) unique samples (and 107258 total alleles; 12.1%) available for MCPH1-D.

Min. 1st Qu. Median Mean 3rd Qu. Max.
0.033 0.5634 0.7737 0.6729 0.8357 1
***Figure 55.*** _Distribution of the frequency of the "derived" allele of *MCPH1* across the world, excluding the "proxy" SNPs._

Figure 55. Distribution of the frequency of the “derived” allele of MCPH1 across the world, excluding the “proxy” SNPs.

Due to this high proportion of the data being represented by “proxy” SNPs, I also conducted separate analyses excluding these SNPs.

New samples

Moreover, 107 are new samples from 85 unique (meta)populations, compared to the 59 samples in 56 (meta)populations in the original Evans et al. (2005). These new samples are distributed as:

Africa Eurasia America Papunesia
12 86 5 4

and the corresponding new (meta)populations as:

Africa Eurasia America Papunesia
12 64 5 4
***Figure 56.*** _Distribution of the "original" and "new" samples of *MCPH1*-D across the world._

Figure 56. Distribution of the “original” and “new” samples of MCPH1-D across the world.

The original Dediu & Ladd (2007) samples

These are the same for ASPM-D and MCPH1-D:

Africa Eurasia America Papunesia
15 37 5 2

and the corresponding new (meta)populations as:

Africa Eurasia America Papunesia
14 35 5 2
***Figure 57.*** _Distribution of the "original" and "new" samples of *MCPH1*-D across the world._

Figure 57. Distribution of the “original” and “new” samples of MCPH1-D across the world.

Putting tone and genes together

When combining the linguistic and genetic data, we are left with 175 unique samples in 129 unique (meta)populations speaking 321 unique “languages” (i.e., Glottolog codes) (from now on, denoted as 175:129:321), of which:

Information for Number of samples:(meta)pops:languages Missing samples:(meta)pops:languages
tone binary 175:129:321 0:0:0 = {} : {} : {}
tone 3-way 170:124:314 5:5:7 = {SA001471N, SA001477T, SA001487U, SA001491P, SA001681Q} : {Burunge, Hazara, Mozabite, Oroqen, Xibe} : {buru1320, efee1239, gyel1242, haza1239, oroq1238, tumz1238, xibe1242}
tone counts 170:124:314 5:5:7 = {SA001471N, SA001477T, SA001487U, SA001491P, SA001681Q} : {Burunge, Hazara, Mozabite, Oroqen, Xibe} : {buru1320, efee1239, gyel1242, haza1239, oroq1238, tumz1238, xibe1242}
ASPM-D 170:127:319 5:2:2 = {FINRISK, GenDan, GenNed5, KRGDB, Qatari} : {Dutch, Qatari} : {dutc1256, gulf1241}
MCPH1-D 166:128:320 9:1:1 = {gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish} : {Bulgarian} : {bulg1262}
ASPM-D & MCPH1-D 161:126:318 14:3:3 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari} : {Bulgarian, Dutch, Qatari} : {bulg1262, dutc1256, gulf1241}
tone binary & ASPM-D & MCPH1-D 161:126:318 14:3:3 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari} : {Bulgarian, Dutch, Qatari} : {bulg1262, dutc1256, gulf1241}
tone 3-way & ASPM-D & MCPH1-D 156:121:311 19:8:10 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari, SA001471N, SA001477T, SA001487U, SA001491P, SA001681Q} : {Bulgarian, Burunge, Dutch, Hazara, Mozabite, Oroqen, Qatari, Xibe} : {bulg1262, buru1320, dutc1256, efee1239, gulf1241, gyel1242, haza1239, oroq1238, tumz1238, xibe1242}
tone counts & ASPM-D & MCPH1-D 156:121:311 19:8:10 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari, SA001471N, SA001477T, SA001487U, SA001491P, SA001681Q} : {Bulgarian, Burunge, Dutch, Hazara, Mozabite, Oroqen, Qatari, Xibe} : {bulg1262, buru1320, dutc1256, efee1239, gulf1241, gyel1242, haza1239, oroq1238, tumz1238, xibe1242}

Some pair-wise differences in terms of samples:(meta)populations:languages with data:

Present in… … but absent from samples:(meta)pops:languages
tone binary tone 3-way (and counts) 5:5:7 = {SA001471N, SA001477T, SA001487U, SA001491P, SA001681Q} : {Burunge, Hazara, Mozabite, Oroqen, Xibe} : {buru1320, efee1239, gyel1242, haza1239, oroq1238, tumz1238, xibe1242}
tone binary ASPM-D 5:2:2 = {FINRISK, GenDan, GenNed5, KRGDB, Qatari} : {Dutch, Qatari} : {dutc1256, gulf1241}
tone binary MCPH1-D 9:1:1 = {gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish} : {Bulgarian} : {bulg1262}
tone binary ASPM-D & MCPH1-D 14:3:3 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari} : {Bulgarian, Dutch, Qatari} : {bulg1262, dutc1256, gulf1241}
tone 3-way (and counts) ASPM-D 5:2:2 = {FINRISK, GenDan, GenNed5, KRGDB, Qatari} : {Dutch, Qatari} : {dutc1256, gulf1241}
tone 3-way (and counts) MCPH1-D 9:1:1 = {gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish} : {Bulgarian} : {bulg1262}
tone 3-way (and counts) ASPM-D & MCPH1-D 14:3:3 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari} : {Bulgarian, Dutch, Qatari} : {bulg1262, dutc1256, gulf1241}

Stats

tone1 (is there tone?)

I kept only the entries with non-missing data for the tone1, ASPM-D and MCPH1-D, and if there are more than one possible languages or allele frequencies for a given sample, I only kept those entries that have different tone or allele data. The resulting dataset has 181 observations, distributed among 119 unique Glottolg codes in 35 families (ranging from a minimum of 1 language per family to a maximum of 48, with a mean 5.2 and median 2 languages per family) and 4 macroareas.

There are 161:126:119 unique samples:(meta)populations:languages retained, dropping 14:3:202 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari} : {Bulgarian, Dutch, Qatari} : {adze1240, ajie1238, amar1272, ambu1247, anei1239, apma1241, arak1252, arib1241, arop1243, aros1241, aulu1238, awtu1239, ayiw1239, baba1268, bahi1254, bann1247, bign1238, bili1260, boik1241, bulg1262, caro1242, cham1313, chek1238, chuu1238, dehu1237, dumb1241, dutc1256, east2443, east2447, fiji1243, futu1245, fwai1237, gapa1238, geez1241, gela1263, gilb1244, gulf1241, guma1254, hali1244, hang1263, hano1246, hmon1264, hoav1238, iaai1238, iatm1242, idak1243, idun1242, iris1253, iwam1256, juho1239, kaia1245, kair1263, kamb1297, kapi1249, kara1486, kaul1240, kela1255, kele1258, kiku1240, kili1267, kire1240, koko1269, kosr1238, kuan1247, kuan1248, kuma1276, kung1261, kwai1243, kwam1251, kwam1252, kwas1243, kwom1262, labu1248, lala1268, lame1260, lauu1247, lena1238, lese1243, lewo1242, long1395, loni1238, lonw1238, louu1245, lusi1240, maee1241, mais1250, male1289, malo1243, mana1295, mana1298, maor1246, mars1254, masa1299, matu1261, mbal1255, mbul1263, mehe1243, meke1243, mele1250, mina1269, ming1252, moch1256, moki1238, moks1248, mono1273, motl1237, motu1246, mudu1242, muri1260, muso1238, muss1246, muyu1244, naka1262, nali1244, nama1264, nami1256, natu1246, naur1243, ndon1254, neha1247, neng1238, ngan1300, niua1240, niue1239, nort2646, nort2836, nort2845, nuku1260, onto1237, paam1238, pate1247, patp1243, pile1238, ping1243, pohn1238, port1285, pulu1242, qima1242, raoo1244, rapa1244, renn1242, rotu1241, rovi1238, russ1264, saaa1240, saam1283, saka1289, sali1295, samo1305, sapo1253, scot1243, siar1238, siee1239, sina1266, sioo1240, sobe1238, sons1242, sout2642, sout2679, sout2807, sout2856, sout2866, sout2869, stan1318, sude1239, surs1246, tahi1242, tain1252, taki1248, tawa1275, tean1237, teop1238, tiga1245, tigr1271, tiri1258, toab1237, toba1266, toke1240, tong1325, tsot1241, tswa1253, tuam1242, tuml1238, tung1290, tuva1244, ulit1238, urav1235, urip1239, vinm1237, waim1251, wall1257, wata1253, west2500, west2519, woga1249, wole1240, xamt1239, xara1244, yabe1254, yess1239, yima1243, zulu1248}.

  Africa Eurasia America Papunesia Sum
No 9 100 4 7 120
Yes 27 26 6 2 61
Sum 36 126 10 9 181
***Figure 58.*** _Distribution of *tone1*._

Figure 58. Distribution of tone1.

***Figure 59.*** _Map of *tone1*._

Figure 59. Map of tone1.

***Figure 60.*** _Relationship between *tone1*, *ASPM*-D and *MCPH1*-D._

Figure 60. Relationship between tone1, ASPM-D and MCPH1-D.

Regressions

glmer

All data
  • null model: R2 = 0.0%1, ICC = 70.4%2 (but generates warnings: Model is nearly unidentifiable: very large eigenvalue)
  • macroarea: R2 = 23.3%, pmacroarea/null = 0.000823
  • ASPM:
    • by itself: R2 = 10.0%, β = -1.00 ± 0.37, pASPM/null = 0.0041
    • quadratic: R2 = 10.7%, βASPM2 = -0.97 ± 0.38, pASPM2/ASPM = 0.6
    • with macroarea: R2 = 24.4%, β = -0.37 ± 0.45, pmacroarea/ASPM = 0.028, pASPM/macroarea = 0.42
  • MCPH1:
    • by itself: R2 = 9.4%, β = -1.04 ± 0.39, pMCPH1/null = 0.0064
    • quadratic: R2 = 9.3%, βMCPH12 = -1.01 ± 0.39, pMCPH12/MCPH1 = 0.21
    • with macroarea: R2 = 24.1%, β = -0.39 ± 0.57, pmacroarea/MCPH1 = 0.021, pMCPH1/macroarea = 0.5
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 13.4%, βASPM = -0.72 ± 0.40, pASPM/MCPH1 = 0.074, βMCPH1 = -0.62 ± 0.40, pMCPH1/ASPM = 0.12, pASPM+MCPH1/null = 0.0049,
    • interaction: R2 = 13.2%, pASPM:MCPH1/ASPM+MCPH1 = 0.86
Alleles on macroarea

To better understand this overlap between family, macroarea and the two “derived” alleles, I regressed (separately) the ASPM-D and MCPH1-D on the macroarea, using mixed-effects beta regression (after replacing all \(0.0\) values by \(10^{-7}\) and all \(1.0\) by \(1.0-10^{-7}\), respectively) with language family as random effect:

  • the alleles are very strongly clustered within families:
    • ASPM: ICC = 100.0%
    • MCPH1: ICC = 100.0%
  • macroarea predicts their distribution very strongly:
    • ASPM: p = 3.4e-16, R2 = 57.9%
    • MCPH1: p = 3.1e-12, R2 = 70.3%
  • separating Africa vs the rest of the world seems to drive most of this effect (both alleles have lower frequencies in Africa):
    • ASPM: p = 2.3e-14, R2 = 39.2%
    • MCPH1: p = 3.2e-09, R2 = 32.6%
Randomization

For these randomization analyses there are several important parameters:

Parameter Meaning Values
permute what to permute? nothing = the original data
tone = permute the tone variable
alleles-together = permute the two alleles together
alleles-independent = permute the two alleles separately, i.e., each is independently permuted
within how are the permutations constrained? unrestricted = all the observations are freely permuted (i.e., there are no constraints, no structure in the data is preserved)
families = only observations within the same language family are permuted (i.e., the structure of the families is preserved)
macroareas = only observations within the same macroarea are permuted (i.e., the structure of the macroareas is preserved)
macroarea how do we control for macroareas? none = no control for macroareas at all
fixef = as fixed effects

I performed 1000 independent replications of each of these parameter combinations, and below are the distributions of the permuted values versus the original ones (i.e., those obtained on the original, non-permuted data).

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 4% 6% 0% 4% 0%
unrestricted none alleles-together 0% 5% 4% 0% 5% 2%
unrestricted none alleles-independent 1% 6% 6% 0% 6% 1%
unrestricted fixef tone 0% 5% 5% 8% 5% 25%
unrestricted fixef alleles-together 68% 6% 7% 15% 4% 23%
unrestricted fixef alleles-independent 68% 5% 6% 16% 6% 20%
macroareas none tone 0% 95% 42% 4% 86% 28%
macroareas none alleles-together 26% 76% 10% 7% 59% 73%
macroareas none alleles-independent 32% 83% 20% 15% 66% 78%
macroareas fixef tone 0% 7% 7% 11% 6% 29%
macroareas fixef alleles-together 65% 5% 5% 19% 5% 35%
macroareas fixef alleles-independent 66% 4% 5% 20% 4% 35%
families none tone 2% 16% 2% 3% 14% 36%
families none alleles-together 2% 11% 3% 5% 5% 16%
families none alleles-independent 2% 16% 13% 10% 12% 20%
families fixef tone 1% 8% 3% 16% 11% 74%
families fixef alleles-together 66% 4% 5% 46% 2% 16%
families fixef alleles-independent 66% 3% 5% 37% 3% 22%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 61.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 100% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -81.1, mean = -0.81, *p* = 0), 82.7%, when controlling for the macroarea (*t*(999) = -32.0, mean = -0.45, *p* = 2.2e-155), and 82.2% when controlling for both macroarea and *MCPH1* (*t*(999) = -30.5, mean = -0.45, *p* = 4.9e-145). For *MCPH1*-D (right): 100% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -107.4, mean = -0.59, *p* = 0), 68.7% when controlling for the macroarea (*t*(999) = -15.5, mean = -0.38, *p* = 3.9e-49), and 67.6% when controlling for both macroarea and *ASPM* (*t*(999) = -14.3, mean = -0.37, *p* = 1.7e-42)._

Figure 61. Results for 1000 restricted samplings. For ASPM-D (left): 100% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -81.1, mean = -0.81, p = 0), 82.7%, when controlling for the macroarea (t(999) = -32.0, mean = -0.45, p = 2.2e-155), and 82.2% when controlling for both macroarea and MCPH1 (t(999) = -30.5, mean = -0.45, p = 4.9e-145). For MCPH1-D (right): 100% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -107.4, mean = -0.59, p = 0), 68.7% when controlling for the macroarea (t(999) = -15.5, mean = -0.38, p = 3.9e-49), and 67.6% when controlling for both macroarea and ASPM (t(999) = -14.3, mean = -0.37, p = 1.7e-42).

brms

tone1 on ASPM-D and MCPH1-D in a mixed-effects Bayesian framework (using brms) with macroarea, language family and (meta)population as (nested) random effects. The ROPE is the region of practical equivalence around 0.0, usually [-0.1, 0.1] but may vary by regression type" the idea is that the HDI should have an as small intersection as possible with the ROPE. Another take is represented by the pROPE which is the proportion of the whole posterior distribution (i.e., 100%HDI) inside the ROPE; so, it can be interpreted like a “classic” p-value.

  • ASPM only:
    • β = -0.69, 89%HDI = [-1.59, 0.25]
    • posterior probability p(β<0) = 0.89 (evidence ratio = 7.9), p(β=0) = 0.73 (evidence ratio = 2.8)
    • ROPE4 = [-0.18, 0.18], % HDI inside ROPE = 13.3%; pROPE = 0.118
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(71%:29%) K>]: moderate evidence for null against ASPM (BF=3.83), LOO=0.70 [SE=1.43], WAIC=0.92 [SE=1.19], KFOLD=4.48 [SE=3.46]5
  • MCPH1 only:
    • β = -0.63, 89%HDI = [-1.66, 0.46]
    • posterior probability p(β<0) = 0.83 (evidence ratio = 5), p(β=0) = 0.76 (evidence ratio = 3.2)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 15.2%; pROPE = 0.135
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(61%:39%) K>]: moderate evidence for null against MCPH1 (BF=3.17), LOO=-0.01 [SE=1.03], WAIC=0.45 [SE=0.77], KFOLD=2.33 [SE=2.31]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B> L= W=(79%:21%) K>]: moderate evidence for null against both (BF=9.56), LOO=1.30 [SE=1.53], WAIC=1.35 [SE=1.44], KFOLD=4.67 [SE=3.70]
    • interaction:
      • posterior probability p(=0) = 0.82 (evidence ratio = 4.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 21.5%; pROPE = 0.134
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L> W=(46%:54%) K>]: moderate evidence for no interaction against with interaction (BF=3.06), LOO=0.88 [SE=0.81], WAIC=-0.14 [SE=0.46], KFOLD=6.05 [SE=3.43]
    • ASPM (partial):
      • β = -0.61, 89%HDI = [-1.62, 0.32]
      • posterior probability p(β<0) = 0.84 (evidence ratio = 5.3), p(β=0) = 0.78 (evidence ratio = 3.6)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 17.6%; pROPE = 0.156
    • MCPH1 (partial):
      • β = -0.46, 89%HDI = [-1.55, 0.78]
      • posterior probability p(β<0) = 0.75 (evidence ratio = 2.9), p(β=0) = 0.8 (evidence ratio = 4)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 19.4%; pROPE = 0.173
***Figure 62.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 62.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 62. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 63.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 63.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 63. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 64.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 64.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 64. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 65.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 65.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 65. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Mediation and path analysis

Here, I try to disentangle the fact that macroarea is a very good predictor of tone1, but also of the frequency of the two alleles, from any effect that the alleles might have on tone1. For this, I conducted mediation analysis and path analysis, where I model the effect of macroarea on tone1 as partially mediated by the two alleles.

Please note that there are several technical issues with these approaches:

  • for mediation analysis, the method used (as implemented by function mediate in package mediation):

    • cannot deal with a factor with several levels → I focused on the contrast between Africa and the rest of the world;
    • cannot deal with language family as random effect → I use “flat” regressions throughout, but I did perform restricted sampling as well as a method to control for family.
  • to adress these issues, I also conducted Bayesian mediation analysis (using brms) with logistic regression for the outcome, beta regression for the “derived” allele frequencies, and family and (meta)population as random effects (the macroarea cannot be a random effect as it is the treatment as Africa vs the rest of the world).

  • for path analysis, the method used (as implemented by function sem with robust estimators in package lavaan):

    • cannot deal with binary variables unless they are either converted to numeric (0 vs 1) or ordered (i.e., assume that there is an intrinsic ordering between the two values), affecting both the binary contrast between Africa and the rest of the world (coded as Africa=1, or ordered as “rest of the world” < “Africa”) and tone1 (coded as Yes=1, or No < Yes); I tested both codings separately;
    • cannot deal with language family as random effect, but I did perform restricted sampling as well as a method to control for family.

Mediation analysis

Figure 66. Graphical representation of the mediation model for the two alleles considered separately. Blue = direct effect of macroarea on tone1; red = indirect effect mediatated by the alleles.

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 0.49 (0.33, 0.63), p=0, decomposed into:

  • average direct effect (ADE): 0.27 (0.08, 0.47), p=0.008, and

  • average indirect effect (ACME) mediated by ASPM-D: 0.22 (0.11, 0.34), p=0, mediating 44.9% (19.1%, 79.5%), p=0 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.25 ±0.16, p=7.7e-13, and
    • effect of ASPM-D on tone: -0.90 ±0.24, p=0.00015.

For MCPH1-D:

  • TE: 0.50 (0.34, 0.65), p=0, decomposed into:

  • ADE: 0.55 (0.19, 0.75), p=0.002, and

  • ACME: -0.05 (-0.22, 0.25), p=0.49, mediating -14.7% (-51.3%, 56.8%), p=0.49 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.19 ±0.09, p=9.9e-59, and
    • effect of MCPH1-D on tone: 0.20 ±0.38, p=0.6.
Restricted sampling
***Figure 67.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM*-D and *MCPH1*-D; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted)._

Figure 67. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM-D and MCPH1-D; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted).

For ASPM-D:

  • TE: mean = 0.38, median = 0.38; 44.5% significant at α-level 0.05 and 72.8% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 134.2, p = 0;

  • ADE: mean = 0.28, median = 0.28; 8.2% significant at α-level 0.05 and 29.6% significant at α-level 0.10; 99.6% > 0.0; one-sample one-sided t-test vs 0: t(999) = 87.2, p = 0;

  • ACME: mean = 0.094, median = 0.091; 3.6% significant at α-level 0.05 and 20.1% significant at α-level 0.10; 99.5% > 0.0; one-sample one-sided t-test vs 0: t(999) = 61.4, p = 0;

  • β(Africa → allele): mean = -0.86, median = -0.87; 79.8% significant at α-level 0.05 and 96.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -211.9, p = 0;

  • β(allele → tone | Africa): mean = -0.61, median = -0.6; 10.2% significant at α-level 0.05 and 27.7% significant at α-level 0.10; 99.1% < 0.0; one-sample one-sided t-test vs 0: t(999) = -60.0, p = 0.

For MCPH1-D:

  • TE: mean = 0.38, median = 0.39; 44.3% significant at α-level 0.05 and 72.6% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 133.1, p = 0;

  • ADE: mean = 0.41, median = 0.44; 6.0% significant at α-level 0.05 and 18.9% significant at α-level 0.10; 96.9% > 0.0; one-sample one-sided t-test vs 0: t(999) = 74.0, p = 0;

  • ACME: mean = -0.029, median = -0.052; 0.1% significant at α-level 0.05 and 1.4% significant at α-level 0.10; 35.7% > 0.0; one-sample one-sided t-test vs 0: t(999) = -6.2, p = 1;

  • β(Africa → allele): mean = -2.5, median = -2.5; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -884.5, p = 0;

  • β(allele → tone | Africa): mean = 0.42, median = 0.42; 0.2% significant at α-level 0.05 and 1.5% significant at α-level 0.10; 25.5% < 0.0; one-sample one-sided t-test vs 0: t(999) = 21.4, p = 1.

Given the low sample size N = 35 unique families, relatively few effect sizes are big enough to be significant for each individual analysis; however, there are many more significant ACMEs for ASPM-D than for MCPH1-D: 10.2% vs 0.2% (51.0 times) for α-level 0.05, and 27.7% vs 1.5% (18.5 times) for α-level 0.10.

brms

Figure 68. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 69. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 70. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

All data

With Africa and tone1 coded numerically, the model fits the data very well6 (χ2(1)=0.22, p=0.64; CFI=1.00, TLI=1.01, NNFI=1.01 and RFI=1.00):

Figure 71. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as numeric binary (tone_bin_num with Yes=1 and Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

## lavaan 0.6-8 ended normally after 25 iterations
## 
##   Estimator                                         ML
##   Optimization method                           NLMINB
##   Number of model parameters                         8
##                                                       
##   Number of observations                           181
##                                                       
## Model Test User Model:
##                                                       
##   Test statistic                                 0.225
##   Degrees of freedom                                 1
##   P-value (Chi-square)                           0.635
## 
## Model Test Baseline Model:
## 
##   Test statistic                               371.522
##   Degrees of freedom                                 6
##   P-value                                        0.000
## 
## User Model versus Baseline Model:
## 
##   Comparative Fit Index (CFI)                    1.000
##   Tucker-Lewis Index (TLI)                       1.013
## 
## Loglikelihood and Information Criteria:
## 
##   Loglikelihood user model (H0)               -448.206
##   Loglikelihood unrestricted model (H1)       -448.094
##                                                       
##   Akaike (AIC)                                 912.413
##   Bayesian (BIC)                               938.000
##   Sample-size adjusted Bayesian (BIC)          912.664
## 
## Root Mean Square Error of Approximation:
## 
##   RMSEA                                          0.000
##   90 Percent confidence interval - lower         0.000
##   90 Percent confidence interval - upper         0.154
##   P-value RMSEA <= 0.05                          0.704
## 
## Standardized Root Mean Square Residual:
## 
##   SRMR                                           0.005
## 
## Parameter Estimates:
## 
##   Standard errors                           Robust.sem
##   Information                                 Expected
##   Information saturated (h1) model          Structured
## 
## Regressions:
##                    Estimate  Std.Err  z-value  P(>|z|) ci.lower ci.upper
##   tone_bin_num ~                                                        
##     Africa_num        0.390    0.166    2.351    0.019    0.065    0.716
##     ASPM_z           -0.144    0.035   -4.163    0.000   -0.212   -0.076
##     MCPH1_z           0.025    0.061    0.410    0.682   -0.095    0.145
##   ASPM_z ~                                                              
##     Africa_num       -1.249    0.111  -11.254    0.000   -1.467   -1.032
##   MCPH1_z ~                                                             
##     Africa_num       -2.190    0.081  -27.039    0.000   -2.349   -2.031
##    Std.lv  Std.all
##                   
##     0.390    0.330
##    -0.144   -0.305
##     0.025    0.053
##                   
##    -1.249   -0.500
##                   
##    -2.190   -0.877
## 
## Variances:
##                    Estimate  Std.Err  z-value  P(>|z|) ci.lower ci.upper
##    .tone_bin_num      0.165    0.015   10.844    0.000    0.135    0.195
##    .ASPM_z            0.746    0.074   10.144    0.000    0.602    0.890
##    .MCPH1_z           0.230    0.039    5.899    0.000    0.154    0.307
##    Std.lv  Std.all
##     0.165    0.740
##     0.746    0.750
##     0.230    0.232
## 
## R-Square:
##                    Estimate
##     tone_bin_num      0.260
##     ASPM_z            0.250
##     MCPH1_z           0.768

Likewise, with Africa and tone1 coded as ordered binary factors, the model also fits the data very well (χ2(1)=0.57, p=0.45; CFI=1.00, TLI=1.07, NNFI=1.07 and RFI=0.92):

Figure 72. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as ordered binary factors (tone_bin_ord with No < Yes, and Africa_ord with outside Africa < in Africa); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Restricted sampling

Here I use only the numerical coding.

***Figure 73.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 73. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

  • models fits:

    • 94.7% of the p-values are not significant
    • mean(CFI) = 0.99, median(CFI) = 1, sd(CFI) = 0.01, IQR(CFI) = 0.02
    • mean(TLI) = 0.97, median(TLI) = 0.99, sd(TLI) = 0.1, IQR(TLI) = 0.16
    • mean(NNFI) = 0.97, median(NNFI) = 0.99, sd(NNFI) = 0.1, IQR(NNFI) = 0.16
    • mean(RFI) = 0.9, median(RFI) = 0.92, sd(RFI) = 0.09, IQR(RFI) = 0.14
  • Africa → ASPM-D: mean = -0.87, median = -0.89, sd = 0.12, IQR = 0.17, 100.0% < 0; 98.7% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -2.2e+02, p = 0;

  • Africa → MCPH1-D: mean = -2.5, median = -2.5, sd = 0.086, IQR = 0.12, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -9e+02, p = 0;

  • Africa → tone1: mean = 0.43, median = 0.44, sd = 0.32, IQR = 0.46, 89.5% > 0; 12.8% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 41, p = 3.2e-219;

  • ASPM-D → tone1: mean = -0.11, median = -0.11, sd = 0.058, IQR = 0.089, 98.6% < 0; 36.2% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -62, p = 0;

  • MCPH1-D → tone1: mean = 0.041, median = 0.041, as = 0.11, IQR = 0.17, 36.7% < 0; 0.9% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 11, p = 1.

Machine Learning techniques

Here I apply various “machine learning” techniques to explore how well the macroarea and the two alleles predict tone1. For these techniques, in general I:

  1. fit the model to the full data and estimate how well these modes fit, but also
  2. repeatedly split the data into a training set the complementary test set; the first usually contains a random subset of 80% of the data and is used to fit the model, while the second, containing the remaining 20% of the data, is used to check how well the model generalizes to new data.

Thus, these techniques can:

  • quantify the amount of information about tone contained by macroarea and the alleles,
  • but also give an estimate of the relative importance of these variables as predictors.

Decision trees

Including macroarea

Using the frequency of the two alleles and the macroarea as predictors, the fit to the data is: accuracy = 77.3%, sensitivity = 71.7%, specificity = 79.3%, precision = 54.1%, and recall = 71.7%.

***Figure 74.*** _Decision tree on the full data using the two alleles and *macroarea*. `ASPM.D` = *ASPM*-D._

Figure 74. Decision tree on the full data using the two alleles and macroarea. ASPM.D = ASPM-D.

On the 100 training/testing sets, the fit is: accuracy = 77.1% ±6.6%, sensitivity = 71.6% ±15.2%, specificity = 79.3% ±6.8%, precision = 52.9% ±12.4%, recall = 71.6% ±15.2%.

***Figure 75.*** _The success of generalising to the testing sets from the training sets (yellow boxplots) compared to the success on the full data (red segments)._

Figure 75. The success of generalising to the testing sets from the training sets (yellow boxplots) compared to the success on the full data (red segments).

Excluding macroarea

When using the frequency of the two alleles only as predictors, the fit to the data is: accuracy = 75.1%, sensitivity = 75.0%, specificity = 75.2%, precision = 39.3%, and recall = 75.0%:

***Figure 76.*** _Decision tree on the full data using the two alleles only. `ASPM.D` = *ASPM*-D, `MCPH1.D` = *MCPH1*-D._

Figure 76. Decision tree on the full data using the two alleles only. ASPM.D = ASPM-D, MCPH1.D = MCPH1-D.

On the 100 training/testing sets,the fit is: accuracy = 70.1% ±7.6%, sensitivity = 61.3% ±19.1%, specificity = 76.2% ±8.7%, precision = 44.0% ±23.0%, recall = 61.3% ±19.1%.

***Figure 77.*** _The success of generalising to the testing sets from the training sets (yellow boxplots) compared to the success on the full data (red segments)._

Figure 77. The success of generalising to the testing sets from the training sets (yellow boxplots) compared to the success on the full data (red segments).

Random forests

I use two methods: random forests as implemented by randomForest() in package randomForest, and conditional random forests as implemented by cforest() in package partykit. As (conditional) random forests do internal bootstrapping, there is no need for the explicit training/testing set repeated refitting.

Including macroarea

When using the frequency of the two alleles and the macroarea as predictors, the models fit to the full data is:

  • random forests: accuracy = 77.7% ±0.8%, sensitivity = 68.9% ±1.9%, specificity = 81.6% ±0.4%, precision = 62.0% ±1.0%, recall = 68.9% ±1.9%,
  • conditional random forests: accuracy = 84.3% ±0.7%, sensitivity = 78.8% ±0.5%, specificity = 86.8% ±0.9%, precision = 73.0% ±2.0%, recall = 78.8% ±0.5%.
***Figure 78.*** _The success of the two random forest methods on the full data._

Figure 78. The success of the two random forest methods on the full data.

***Figure 79.*** _Variable importance using three methods: mean decrease in accuracy, mean decrease of the Gini coeficient, and unconditional importance. `ASPM_freq_wavg` = *ASPM*-D, `MCPH1_freq_wavg` = *MCPH1*-D._

Figure 79. Variable importance using three methods: mean decrease in accuracy, mean decrease of the Gini coeficient, and unconditional importance. ASPM_freq_wavg = ASPM-D, MCPH1_freq_wavg = MCPH1-D.

Excluding macroarea

When using the frequency of the two alleles only, the models fit the full as:

  • random forests: accuracy = 70.7% ±1.0%, sensitivity = 56.3% ±1.4%, specificity = 78.6% ±0.8%, precision = 59.0% ±1.8%, recall = 56.3% ±1.4%,
  • conditional random forests: accuracy = 82.1% ±0.5%, sensitivity = 81.8% ±0.7%, specificity = 82.3% ±0.6%, precision = 60.5% ±1.6%, recall = 81.8% ±0.7%.
***Figure 80.*** _The success of the two random forest methods on the full data._

Figure 80. The success of the two random forest methods on the full data.

***Figure 81.*** _Variable importance using three methods: mean decrease in accuracy, mean decrease of the Gini coeficient, and unconditional importance. `ASPM_freq_wavg` = *ASPM*-D, `MCPH1_freq_wavg` = *MCPH1*-D._

Figure 81. Variable importance using three methods: mean decrease in accuracy, mean decrease of the Gini coeficient, and unconditional importance. ASPM_freq_wavg = ASPM-D, MCPH1_freq_wavg = MCPH1-D.

Diachronic analyses

Here I try various analyses that explicitly take into account the diachronic nature of the processes.

The families with more than 2 tips are:

***Figure 82.*** _Phylogenies with *tone1* (0="No", 1="Yes", *ASPM*-D and *MCHP1*-D for the families with at least 2 languages._

Figure 82. Phylogenies with tone1 (0=“No,” 1=“Yes,” ASPM-D and MCHP1-D for the families with at least 2 languages.

It can be seen that, unfortunately, there are very few families with more than 2 languages with data (17), and even for those with relatively many languages, there is very little variation in tone1 and in the frequencies of the two “derived” alleles. Unfortunately, combined with the issues concerning branch length for language family trees, this precludes the estimation of correlated evolution or phylogenetic regression methods.

tone2 (is there complex tone?)

I kept only the entries with non-missing data for the tone2, ASPM-D and MCPH1-D, and if there are more than one possible languages or allele frequencies for a given sample, I only kept those entries that have different tone or allele data. The resulting dataset has 180 observations, distributed among 118 unique Glottolg codes in 35 families (ranging from a minimum of 1 language per family to a maximum of 47, with a mean 5.1 and median 2 languages per family) and 4 macroareas.

There are 156:121:118 unique samples:(meta)populations:languages retained, dropping 19:8:203 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari, SA001471N, SA001477T, SA001487U, SA001491P, SA001681Q} : {Bulgarian, Burunge, Dutch, Hazara, Mozabite, Oroqen, Qatari, Xibe} : {adze1240, ajie1238, amar1272, ambu1247, anei1239, apma1241, arak1252, arib1241, arop1243, aros1241, aulu1238, awtu1239, ayiw1239, baba1268, bahi1254, bann1247, bign1238, bili1260, boik1241, bulg1262, buru1320, caro1242, cham1313, chek1238, chuu1238, dehu1237, dumb1241, dutc1256, east2443, east2447, efee1239, fiji1243, futu1245, gapa1238, geez1241, gela1263, gilb1244, gulf1241, guma1254, gyel1242, hali1244, hang1263, hano1246, haza1239, hmon1264, hoav1238, iaai1238, iatm1242, idak1243, idun1242, iris1253, iwam1256, juho1239, kaia1245, kair1263, kamb1297, kapi1249, kara1486, kaul1240, kela1255, kele1258, kili1267, kire1240, koko1269, kosr1238, kuan1247, kuan1248, kuma1276, kung1261, kwai1243, kwam1251, kwam1252, kwom1262, labu1248, lala1268, lame1260, lauu1247, lena1238, lewo1242, long1395, loni1238, lonw1238, louu1245, lusi1240, maee1241, mais1250, male1289, malo1243, mana1295, mana1298, maor1246, mars1254, masa1299, matu1261, mbal1255, mbul1263, mehe1243, meke1243, mele1250, mina1269, ming1252, moch1256, moki1238, moks1248, mono1273, motl1237, motu1246, mudu1242, muri1260, muso1238, muss1246, muyu1244, naka1262, nali1244, nami1256, natu1246, naur1243, ndon1254, neha1247, neng1238, ngan1300, niua1240, niue1239, nort2646, nort2836, nort2845, nuku1260, onto1237, oroq1238, paam1238, pate1247, patp1243, pile1238, ping1243, pohn1238, port1285, pulu1242, qima1242, raoo1244, rapa1244, renn1242, rotu1241, rovi1238, russ1264, saaa1240, saam1283, saka1289, sali1295, samo1305, sapo1253, scot1243, siar1238, siee1239, sina1266, sioo1240, sobe1238, sons1242, sout2642, sout2679, sout2807, sout2856, sout2866, sout2869, stan1318, sude1239, surs1246, tahi1242, tain1252, taki1248, tawa1275, tean1237, teop1238, tiga1245, tigr1271, tiri1258, toab1237, toba1266, toke1240, tong1325, tswa1253, tuam1242, tuml1238, tumz1238, tung1290, tuva1244, ulit1238, urav1235, urip1239, vinm1237, waim1251, wall1257, wata1253, west2500, west2519, woga1249, wole1240, xamt1239, xara1244, xibe1242, yabe1254, yess1239, yima1243, zulu1248}.

  Africa Eurasia America Papunesia Sum
No 28 105 9 9 151
Yes 9 18 1 1 29
Sum 37 123 10 10 180
***Figure 83.*** _Distribution of *tone2*._

Figure 83. Distribution of tone2.

***Figure 84.*** _Map of *tone2*._

Figure 84. Map of tone2.

***Figure 85.*** _Relationship between *tone2*, *ASPM*-D and *MCPH1*-D._

Figure 85. Relationship between tone2, ASPM-D and MCPH1-D.

Please note that the distribution of this variable is very skewed, so the results might not be very solid…

Regressions

glmer

All data
  • null model: R2 = 0.0%, ICC = 95.6%
  • macroarea: R2 = 2.0%, pmacroarea/null = 0.5
  • ASPM:
    • by itself: R2 = 1.3%, β = -0.87 ± 0.69, pASPM/null = 0.19
    • quadratic: R2 = 36.6%, βASPM2 = -3.46 ± 2.31, pASPM2/ASPM = 0.049
    • with macroarea: R2 = 2.6%, pmacroarea/ASPM = 0.8, pASPM/macroarea = 0.55
  • MCPH1:
    • by itself: R2 = 1.5%, β = -1.01 ± 0.73, pMCPH1/null = 0.16
    • quadratic: R2 = 3.0%, βMCPH12 = -1.17 ± 0.81, pMCPH12/MCPH1 = 0.22
    • with macroarea: R2 = 2.4%, pmacroarea/MCPH1 = 0.89, pMCPH1/macroarea = 0.62
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 2.0%, βASPM = -0.56 ± 0.78, pASPM/MCPH1 = 0.47, βMCPH1 = -0.68 ± 0.81, pMCPH1/ASPM = 0.39, pASPM+MCPH1/null = 0.29,
    • interaction: R2 = 1.5%, pASPM:MCPH1/ASPM+MCPH1 = 0.76
Randomization
Regressions with randomizations for tone2.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 4% 4% 1% 6% 0%
unrestricted none alleles-together 31% 7% 6% 10% 6% 6%
unrestricted none alleles-independent 32% 7% 7% 9% 6% 4%
unrestricted fixef tone 0% 6% 6% 6% 7% 23%
unrestricted fixef alleles-together 84% 7% 7% 17% 7% 25%
unrestricted fixef alleles-independent 83% 9% 8% 16% 7% 21%
macroareas none tone 0% 4% 3% 1% 10% 1%
macroareas none alleles-together 40% 7% 5% 21% 6% 42%
macroareas none alleles-independent 44% 8% 6% 28% 10% 45%
macroareas fixef tone 0% 4% 4% 7% 4% 22%
macroareas fixef alleles-together 80% 8% 8% 28% 7% 38%
macroareas fixef alleles-independent 80% 9% 8% 25% 8% 37%
families none tone 31% 4% 4% 28% 1% 16%
families none alleles-together 20% 4% 5% 29% 1% 15%
families none alleles-independent 24% 4% 6% 25% 3% 22%
families fixef tone 45% 8% 9% 54% 4% 43%
families fixef alleles-together 80% 4% 6% 43% 3% 18%
families fixef alleles-independent 80% 5% 7% 34% 4% 24%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 86.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 99.6% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -77.3, mean = -0.61, *p* = 0), 99.8%, when controlling for the macroarea (*t*(999) = -75.6, mean = -0.96, *p* = 0), and 99.9% when controlling for both macroarea and *MCPH1* (*t*(999) = -70.9, mean = -1.08, *p* = 0). For *MCPH1*-D (right): 72.9% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -21.7, mean = -0.16, *p* = 7.8e-86), 42.9% when controlling for the macroarea (*t*(999) = 9.6, mean = 0.30, *p* = 1), and 35.1% when controlling for both macroarea and *ASPM* (*t*(999) = 17.1, mean = 0.67, *p* = 1)._

Figure 86. Results for 1000 restricted samplings. For ASPM-D (left): 99.6% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -77.3, mean = -0.61, p = 0), 99.8%, when controlling for the macroarea (t(999) = -75.6, mean = -0.96, p = 0), and 99.9% when controlling for both macroarea and MCPH1 (t(999) = -70.9, mean = -1.08, p = 0). For MCPH1-D (right): 72.9% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -21.7, mean = -0.16, p = 7.8e-86), 42.9% when controlling for the macroarea (t(999) = 9.6, mean = 0.30, p = 1), and 35.1% when controlling for both macroarea and ASPM (t(999) = 17.1, mean = 0.67, p = 1).

brms

  • ASPM only:
    • β = -1.27, 89%HDI = [-2.73, 0.17]
    • posterior probability p(β<0) = 0.93 (evidence ratio = 14), p(β=0) = 0.57 (evidence ratio = 1.4)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 6.1%; pROPE = 0.055
    • comparison ‘null’ vs ‘ASPM’: [B= L> W=(53%:47%) K=]: anecdotal evidence for null against ASPM (BF=1.46), LOO=1.84 [SE=1.14], WAIC=0.10 [SE=1.16], KFOLD=-0.80 [SE=2.10]
  • MCPH1 only:
    • β = -0.91, 89%HDI = [-2.38, 0.58]
    • posterior probability p(β<0) = 0.85 (evidence ratio = 5.5), p(β=0) = 0.7 (evidence ratio = 2.4)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 10.9%; pROPE = 0.097
    • comparison ‘null’ vs ‘MCPH1’: [B= L= W=(41%:59%) K<]: anecdotal evidence for null against MCPH1 (BF=1.63), LOO=0.25 [SE=0.64], WAIC=-0.36 [SE=0.73], KFOLD=-2.43 [SE=1.67]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B> L= W=(30%:70%) K=]: moderate evidence for null against both (BF=3.66), LOO=0.13 [SE=1.39], WAIC=-0.87 [SE=1.44], KFOLD=-1.33 [SE=2.11]
    • interaction:
      • posterior probability p(=0) = 0.75 (evidence ratio = 3)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 15.1%; pROPE = 0.134
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L> W=(57%:43%) K>]: moderate evidence for no interaction against with interaction (BF=3.65), LOO=1.16 [SE=1.00], WAIC=0.29 [SE=0.39], KFOLD=2.31 [SE=1.26]
    • ASPM (partial):
      • β = -1.13, 89%HDI = [-2.71, 0.60]
      • posterior probability p(β<0) = 0.87 (evidence ratio = 6.8), p(β=0) = 0.66 (evidence ratio = 1.9)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 9%; pROPE = 0.08
    • MCPH1 (partial):
      • β = -0.58, 89%HDI = [-2.21, 0.99]
      • posterior probability p(β<0) = 0.73 (evidence ratio = 2.7), p(β=0) = 0.75 (evidence ratio = 3)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 13.7%; pROPE = 0.122
***Figure 87.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 87.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 87. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 88.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 88.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 88. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 89.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 89.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 89. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 90.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 90.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 90. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Mediation and path analysis

Mediation analysis

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 0.14 (-0.01, 0.30), p=0.078, decomposed into:

  • average direct effect (ADE): -0.05 (-0.20, 0.10), p=0.43, and

  • average indirect effect (ACME) mediated by ASPM-D: 0.19 (0.08, 0.31), p=0.004, mediating 133.8% (-419.6%, 802.0%), p=0.082 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.34 ±0.16, p=3.7e-15, and
    • effect of ASPM-D on tone: -1.03 ±0.31, p=0.0011.

For MCPH1-D:

  • TE: 0.11 (-0.02, 0.27), p=0.12, decomposed into:

  • ADE: 0.12 (-0.21, 0.45), p=0.47, and

  • ACME: -0.01 (-0.29, 0.29), p=0.9, mediating -11.4% (-804.5%, 1112.4%), p=0.93 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.19 ±0.09, p=1.2e-61, and
    • effect of MCPH1-D on tone: 0.03 ±0.45, p=0.94.
Restricted sampling
***Figure 91.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM* and *MCPH1*; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted)._

Figure 91. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM and MCPH1; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted).

For ASPM-D:

  • TE: mean = 0.11, median = 0.12; 0.4% significant at α-level 0.05 and 2.3% significant at α-level 0.10; 89.6% > 0.0; one-sample one-sided t-test vs 0: t(999) = 39.7, p = 5.9e-208;

  • ADE: mean = 0.04, median = 0.039; 0.0% significant at α-level 0.05 and 0.0% significant at α-level 0.10; 67.3% > 0.0; one-sample one-sided t-test vs 0: t(999) = 16.0, p = 7.9e-52;

  • ACME: mean = 0.072, median = 0.07; 0.0% significant at α-level 0.05 and 0.1% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 78.5, p = 0;

  • β(Africa → allele): mean = -0.88, median = -0.89; 88.6% significant at α-level 0.05 and 98.7% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -249.8, p = 0;

  • β(allele → tone | Africa): mean = -0.58, median = -0.57; 0.0% significant at α-level 0.05 and 0.4% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -79.8, p = 0.

For MCPH1-D:

  • TE: mean = 0.11, median = 0.11; 0.2% significant at α-level 0.05 and 2.3% significant at α-level 0.10; 82.1% > 0.0; one-sample one-sided t-test vs 0: t(999) = 37.1, p = 1.3e-190;

  • ADE: mean = 0.13, median = 0.14; 0.0% significant at α-level 0.05 and 0.7% significant at α-level 0.10; 75.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 24.8, p = 2.3e-106;

  • ACME: mean = -0.028, median = -0.034; 0.0% significant at α-level 0.05 and 0.3% significant at α-level 0.10; 43.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = -5.4, p = 1;

  • β(Africa → allele): mean = -2.4, median = -2.4; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -927.9, p = 0;

  • β(allele → tone | Africa): mean = 0.26, median = 0.21; 0.0% significant at α-level 0.05 and 0.1% significant at α-level 0.10; 38.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = 11.3, p = 1.

brms

Figure 92. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 93. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 94. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

All data

Coding Africa and tone2 numerically, the model fit is: χ2(1)=0.36, p=0.55; CFI=1.00, TLI=1.01, NNFI=1.01 and RFI=0.99.

Figure 95. Path analysis model with standardised coefficients and significance stars. Here, we coded tone and macroarea (Africa vs non-Africa) as numeric binary (tone_complex_num with Yes=1 and Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

## lavaan 0.6-8 ended normally after 25 iterations
## 
##   Estimator                                         ML
##   Optimization method                           NLMINB
##   Number of model parameters                         8
##                                                       
##   Number of observations                           180
##                                                       
## Model Test User Model:
##                                                       
##   Test statistic                                 0.361
##   Degrees of freedom                                 1
##   P-value (Chi-square)                           0.548
## 
## Model Test Baseline Model:
## 
##   Test statistic                               354.897
##   Degrees of freedom                                 6
##   P-value                                        0.000
## 
## User Model versus Baseline Model:
## 
##   Comparative Fit Index (CFI)                    1.000
##   Tucker-Lewis Index (TLI)                       1.011
## 
## Loglikelihood and Information Criteria:
## 
##   Loglikelihood user model (H0)               -407.836
##   Loglikelihood unrestricted model (H1)       -407.655
##                                                       
##   Akaike (AIC)                                 831.671
##   Bayesian (BIC)                               857.215
##   Sample-size adjusted Bayesian (BIC)          831.879
## 
## Root Mean Square Error of Approximation:
## 
##   RMSEA                                          0.000
##   90 Percent confidence interval - lower         0.000
##   90 Percent confidence interval - upper         0.166
##   P-value RMSEA <= 0.05                          0.630
## 
## Standardized Root Mean Square Residual:
## 
##   SRMR                                           0.006
## 
## Parameter Estimates:
## 
##   Standard errors                           Robust.sem
##   Information                                 Expected
##   Information saturated (h1) model          Structured
## 
## Regressions:
##                      Estimate  Std.Err  z-value  P(>|z|) ci.lower ci.upper
##   tone_complex_num ~                                                      
##     Africa_num         -0.051    0.139   -0.366    0.714   -0.322    0.221
##     ASPM_z             -0.108    0.026   -4.124    0.000   -0.159   -0.056
##     MCPH1_z            -0.005    0.050   -0.093    0.926   -0.102    0.093
##   ASPM_z ~                                                                
##     Africa_num         -1.338    0.101  -13.315    0.000   -1.535   -1.141
##   MCPH1_z ~                                                               
##     Africa_num         -2.189    0.072  -30.443    0.000   -2.330   -2.048
##    Std.lv  Std.all
##                   
##    -0.051   -0.056
##    -0.108   -0.292
##    -0.005   -0.013
##                   
##    -1.338   -0.542
##                   
##    -2.189   -0.887
## 
## Variances:
##                    Estimate  Std.Err  z-value  P(>|z|) ci.lower ci.upper
##    .tone_complx_nm    0.125    0.016    7.848    0.000    0.094    0.157
##    .ASPM_z            0.702    0.072    9.767    0.000    0.561    0.843
##    .MCPH1_z           0.212    0.037    5.748    0.000    0.140    0.284
##    Std.lv  Std.all
##     0.125    0.927
##     0.702    0.706
##     0.212    0.213
## 
## R-Square:
##                    Estimate
##     tone_complx_nm    0.073
##     ASPM_z            0.294
##     MCPH1_z           0.787

Coding Africa and tone2 as ordered binary factors, the model fit is: χ2(1)=0.98, p=0.32; CFI=1.00, TLI=1.01, NNFI=1.01 and RFI=0.79.

Figure 96. Path analysis model with standardised coefficients and significance stars. Here, we coded tone and macroarea (Africa vs non-Africa) as ordered binary factors (tone_complex_ord with No < Yes, and Africa_ord with outside Africa < in Africa); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Restricted sampling

Here I use here only the numerically-coded model.

***Figure 97.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 97. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

It can be seen that:

  • the models fit are:

    • 97.6% of the p-values are not significant
    • mean(CFI) = 0.99, median(CFI) = 1, sd(CFI) = 0.01, IQR(CFI) = 0.01
    • mean(TLI) = 0.98, median(TLI) = 0.99, sd(TLI) = 0.1, IQR(TLI) = 0.15
    • mean(NNFI) = 0.98, median(NNFI) = 0.99, sd(NNFI) = 0.1, IQR(NNFI) = 0.15
    • mean(RFI) = 0.9, median(RFI) = 0.92, sd(RFI) = 0.09, IQR(RFI) = 0.13
  • Africa → ASPM-D: mean = -0.89, median = -0.9, sd = 0.11, IQR = 0.15, 100.0% < 0; 99.8% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -2.5e+02, p = 0;

  • Africa → MCPH1-D: mean = -2.4, median = -2.4, sd = 0.079, IQR = 0.11, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -9.6e+02, p = 0;

  • Africa → tone2: mean = 0.039, median = 0.021, sd = 0.26, IQR = 0.37, 53.6% > 0; 0.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 4.7, p = 1.2e-06;

  • ASPM-D → tone2: mean = -0.071, median = -0.071, sd = 0.027, IQR = 0.037, 99.8% < 0; 5.9% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -83, p = 0;

  • MCPH1-D → tone2: mean = -0.00016, median = -0.0016, as = 0.1, IQR = 0.14, 50.8% < 0; 0.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -0.051, p = 0.48.

Machine Learning techniques

Decision trees

When using the frequency of the two alleles and the macroarea as predictors, the decision tree is trivial: it uniformly predicts just the majority value “No.”

***Figure 98.*** _Decision tree on the full data using the two alleles and macroarea._

Figure 98. Decision tree on the full data using the two alleles and macroarea.

accuracy = 83.9%, sensitivity = NA%, specificity = 83.9%, precision = 0.0%, and recall = NA%.

On the 100 training/testing sets: accuracy = 82.9% ±5.8%, sensitivity = 15.8% ±9.0%, specificity = 83.5% ±5.3%, precision = 0.8% ±4.4%, recall = 15.8% ±9.0%.

***Figure 99.*** _The success of generalising to the testing sets from the training sets (yellow boxplots) compared to the success on the full data (red segments)._

Figure 99. The success of generalising to the testing sets from the training sets (yellow boxplots) compared to the success on the full data (red segments).

Random forests

Including macroarea
  • random forests: accuracy = 84.2% ±0.5%, sensitivity = 58.4% ±11.2%, specificity = 84.9% ±0.4%, precision = 8.8% ±2.6%, recall = 58.4% ±11.2%
  • conditional random forests: accuracy = 87.2% ±0.7%, sensitivity = 97.5% ±4.8%, specificity = 86.9% ±0.7%, precision = 21.2% ±5.2%, recall = 97.5% ±4.8%
***Figure 100.*** _The success of the two random forest methods on the full data._

Figure 100. The success of the two random forest methods on the full data.

***Figure 101.*** _Variable importance using three methods: mean decrease in accuracy, mean decrease of the Gini coeficient, and unconditional importance._

Figure 101. Variable importance using three methods: mean decrease in accuracy, mean decrease of the Gini coeficient, and unconditional importance.

Excluding macroarea
  • random forests: accuracy = 82.2% ±1.0%, sensitivity = 42.8% ±4.4%, specificity = 87.3% ±0.6%, precision = 30.3% ±3.5%, recall = 42.8% ±4.4%
  • conditional random forests: accuracy = 87.3% ±0.2%, sensitivity = 81.2% ±3.1%, specificity = 87.7% ±0.0%, precision = 27.6% ±0.0%, recall = 81.2% ±3.1%
***Figure 102.*** _The success of the two random forest methods on the full data._

Figure 102. The success of the two random forest methods on the full data.

***Figure 103.*** _Variable importance using three methods: mean decrease in accuracy, mean decrease of the Gini coeficient, and unconditional importance._

Figure 103. Variable importance using three methods: mean decrease in accuracy, mean decrease of the Gini coeficient, and unconditional importance.

Tone counts

Here the imputed counts are rounded to the nearest integer; please see below for using the actually predicted values.

I kept only the entries with non-missing data for the tone counts, ASPM-D and MCPH1-D, and if there are more than one possible languages or allele frequencies for a given sample, I only kept those entries that have different tone or allele data. The resulting dataset has 184 observations, distributed among 121 unique Glottolg codes in 35 families (ranging from a minimum of 1 language per family to a maximum of 47, with a mean 5.3 and median 2 languages per family) and 4 macroareas.

There are 156:121:121 unique samples:(meta)populations:languages retained, dropping 19:8:200 = {FINRISK, GenDan, GenNed5, gnomAD_asj, gnomAD_bgr, gnomAD_est, gnomAD_fin, gnomAD_jpn, gnomAD_kor, gnomAD_swe, gnomADexomes_AshkenaziJewish, gnomADgenomes_AshkenaziJewish, KRGDB, Qatari, SA001471N, SA001477T, SA001487U, SA001491P, SA001681Q} : {Bulgarian, Burunge, Dutch, Hazara, Mozabite, Oroqen, Qatari, Xibe} : {adze1240, ajie1238, amar1272, ambu1247, anei1239, apma1241, arak1252, arib1241, arop1243, aros1241, aulu1238, awtu1239, ayiw1239, baba1268, bahi1254, bann1247, bign1238, bili1260, boik1241, bulg1262, buru1320, caro1242, cham1313, chek1238, chuu1238, dehu1237, dumb1241, dutc1256, east2443, east2447, efee1239, fiji1243, futu1245, gapa1238, geez1241, gela1263, gilb1244, gulf1241, guma1254, gyel1242, hali1244, hang1263, hano1246, haza1239, hoav1238, iaai1238, iatm1242, idak1243, idun1242, iris1253, iwam1256, juho1239, kaia1245, kair1263, kamb1297, kapi1249, kara1486, kaul1240, kela1255, kele1258, kili1267, kire1240, koko1269, kosr1238, kuan1248, kuma1276, kung1261, kwai1243, kwam1251, kwam1252, kwom1262, labu1248, lala1268, lame1260, lauu1247, lena1238, lewo1242, long1395, loni1238, lonw1238, louu1245, lusi1240, maee1241, mais1250, male1289, malo1243, mana1295, mana1298, maor1246, mars1254, masa1299, matu1261, mbal1255, mbul1263, mehe1243, meke1243, mele1250, mina1269, ming1252, moch1256, moki1238, moks1248, mono1273, motl1237, motu1246, mudu1242, muri1260, muso1238, muss1246, muyu1244, naka1262, nali1244, nami1256, natu1246, naur1243, ndon1254, neha1247, neng1238, ngan1300, niua1240, niue1239, nort2646, nort2836, nort2845, nuku1260, onto1237, oroq1238, paam1238, pate1247, patp1243, pile1238, ping1243, pohn1238, port1285, pulu1242, qima1242, raoo1244, rapa1244, renn1242, rotu1241, rovi1238, russ1264, saaa1240, saam1283, saka1289, sali1295, samo1305, sapo1253, scot1243, siar1238, siee1239, sina1266, sioo1240, sobe1238, sons1242, sout2642, sout2679, sout2807, sout2856, sout2866, sout2869, stan1318, sude1239, surs1246, tahi1242, taki1248, tawa1275, tean1237, teop1238, tiga1245, tigr1271, tiri1258, toab1237, toba1266, toke1240, tong1325, tswa1253, tuam1242, tuml1238, tumz1238, tung1290, tuva1244, ulit1238, urav1235, urip1239, vinm1237, waim1251, wall1257, wata1253, west2500, west2519, woga1249, wole1240, xamt1239, xara1244, xibe1242, yabe1254, yess1239, yima1243, zulu1248}.

  Africa Eurasia America Papunesia Sum
0 9 98 4 7 118
1 10 6 5 1 22
2 16 3 0 2 21
3 2 5 0 0 7
4 0 8 1 0 9
5 1 4 0 0 5
6 0 2 0 0 2
Sum 38 126 10 10 184
***Figure 104.*** _Distribution of tone *counts*._

Figure 104. Distribution of tone counts.

***Figure 105.*** _Distribution of tone *counts* across the world._

Figure 105. Distribution of tone counts across the world.

***Figure 106.*** _Relationship between tone *counts* (colors) and the two alleles (frequency) by macroarea._

Figure 106. Relationship between tone counts (colors) and the two alleles (frequency) by macroarea.

Regressions

I used a mixed-effects Poisson model.

glmer

All data
  • null model: R2 = 0.0%, ICC = 100.0%
  • the Poisson model is not overdispersed: χ2(182) = 112.6, p = 1
  • macroarea: R2 = 23.8%, pmacroarea/null = 0.013
  • ASPM:
    • by itself: R2 = 7.6%, β = -0.37 ± 0.19, pASPM/null = 0.061
    • quadratic: R2 = 17.9%, βASPM2 = -0.42 ± 0.21, pASPM2/ASPM = 0.12
    • with macroarea: R2 = 24.8%, pmacroarea/ASPM = 0.058, pASPM/macroarea = 0.66
  • MCPH1:
    • by itself: R2 = 9.9%, β = -0.46 ± 0.19, pMCPH1/null = 0.016
    • quadratic: R2 = 10.9%, βMCPH12 = -0.45 ± 0.19, pMCPH12/MCPH1 = 0.19
    • with macroarea: R2 = 24.1%, pmacroarea/MCPH1 = 0.15, pMCPH1/macroarea = 0.64
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 15.7%, βASPM = -0.27 ± 0.20, pASPM/MCPH1 = 0.18, βMCPH1 = -0.37 ± 0.19, pMCPH1/ASPM = 0.043, pASPM+MCPH1/null = 0.022,
    • interaction: R2 = 15.4%, pASPM:MCPH1/ASPM+MCPH1 = 0.86
Randomization

We performed 1000 independent replications:

Regressions with randomizations for tone counts.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 18% 14% 4% 13% 2%
unrestricted none alleles-together 1% 2% 3% 0% 3% 0%
unrestricted none alleles-independent 1% 3% 4% 0% 3% 0%
unrestricted fixef tone 0% 23% 16% 33% 19% 30%
unrestricted fixef alleles-together 81% 2% 3% 16% 3% 12%
unrestricted fixef alleles-independent 81% 4% 3% 13% 4% 6%
macroareas none tone 0% 44% 19% 12% 31% 7%
macroareas none alleles-together 18% 36% 8% 6% 34% 20%
macroareas none alleles-independent 20% 34% 12% 7% 37% 19%
macroareas fixef tone 0% 31% 23% 33% 21% 35%
macroareas fixef alleles-together 79% 3% 4% 23% 4% 26%
macroareas fixef alleles-independent 81% 4% 4% 24% 4% 26%
families none tone 24% 19% 14% 28% 8% 8%
families none alleles-together 9% 16% 12% 32% 4% 4%
families none alleles-independent 10% 20% 20% 40% 8% 8%
families fixef tone 18% 7% 9% 63% 2% 54%
families fixef alleles-together 83% 4% 8% 61% 2% 5%
families fixef alleles-independent 82% 5% 7% 59% 2% 11%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 107.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 100% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -81.5, mean = -0.48, *p* = 0), 96.7%, when controlling for the macroarea (*t*(999) = -52.9, mean = -0.48, *p* = 4.6e-292), and 96.7% when controlling for both macroarea and *MCPH1* (*t*(999) = -53.5, mean = -0.52, *p* = 5e-296). For *MCPH1*-D (right): 99.2% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -70.7, mean = -0.25, *p* = 0), 50.5% when controlling for the macroarea (*t*(999) = 2.8, mean = 0.05, *p* = 1), and 38.2% when controlling for both macroarea and *ASPM* (*t*(999) = 12.6, mean = 0.24, *p* = 1)._

Figure 107. Results for 1000 restricted samplings. For ASPM-D (left): 100% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -81.5, mean = -0.48, p = 0), 96.7%, when controlling for the macroarea (t(999) = -52.9, mean = -0.48, p = 4.6e-292), and 96.7% when controlling for both macroarea and MCPH1 (t(999) = -53.5, mean = -0.52, p = 5e-296). For MCPH1-D (right): 99.2% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -70.7, mean = -0.25, p = 0), 50.5% when controlling for the macroarea (t(999) = 2.8, mean = 0.05, p = 1), and 38.2% when controlling for both macroarea and ASPM (t(999) = 12.6, mean = 0.24, p = 1).

brms

  • ASPM only:
    • β = -0.25, 89%HDI = [-0.64, 0.17]
    • posterior probability p(β<0) = 0.84 (evidence ratio = 5.2), p(β=0) = 0.88 (evidence ratio = 7.5)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 21%; pROPE = 0.187
    • comparison ‘null’ vs ‘ASPM’: [B> L= W>(71%:29%) K>]: moderate evidence for null against ASPM (BF=4.35), LOO=1.00 [SE=1.31], WAIC=0.89 [SE=0.89], KFOLD=4.18 [SE=3.39]
  • MCPH1 only:
    • β = -0.24, 89%HDI = [-0.65, 0.25]
    • posterior probability p(β<0) = 0.8 (evidence ratio = 4), p(β=0) = 0.89 (evidence ratio = 8.1)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 20.4%; pROPE = 0.182
    • comparison ‘null’ vs ‘MCPH1’: [B> L> W>(65%:35%) K>]: moderate evidence for null against MCPH1 (BF=6.59), LOO=1.00 [SE=0.83], WAIC=0.63 [SE=0.61], KFOLD=1.49 [SE=1.40]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L> W>(83%:17%) K>>]: very strong evidence for null against both (BF=46.8), LOO=1.99 [SE=1.23], WAIC=1.58 [SE=1.08], KFOLD=9.05 [SE=3.68]
    • interaction:
      • posterior probability p(=0) = 0.93 (evidence ratio = 13)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 33.8%; pROPE = 0.301
      • comparison ‘no interaction’ vs ‘with interaction’: [B>> L> W>>(68%:32%) K>]: strong evidence for no interaction against with interaction (BF=17.1), LOO=0.63 [SE=0.59], WAIC=0.77 [SE=0.30], KFOLD=2.09 [SE=1.95]
    • ASPM (partial):
      • β = -0.22, 89%HDI = [-0.66, 0.16]
      • posterior probability p(β<0) = 0.81 (evidence ratio = 4.2), p(β=0) = 0.9 (evidence ratio = 8.6)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 24.2%; pROPE = 0.216
    • MCPH1 (partial):
      • β = -0.21, 89%HDI = [-0.64, 0.23]
      • posterior probability p(β<0) = 0.78 (evidence ratio = 3.5), p(β=0) = 0.89 (evidence ratio = 8.1)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 22.4%; pROPE = 0.199
***Figure 108.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 108.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 108. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 109.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 109.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 109. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 110.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 110.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 110. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

Mediation and path analysis

Mediation analysis

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 0.94 (0.40, 1.72), p=0, decomposed into:

  • average direct effect (ADE): -0.16 (-0.69, 0.30), p=0.48, and

  • average indirect effect (ACME) mediated by ASPM-D: 1.11 (0.63, 1.79), p=0, mediating 117.0% (76.3%, 223.9%), p=0 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.34 ±0.15, p=1.6e-15, and
    • effect of ASPM-D on tone: -0.73 ±0.12, p=4.2e-10.

For MCPH1-D:

  • TE: 0.69 (0.32, 1.13), p=0, decomposed into:

  • ADE: 0.44 (-0.44, 1.38), p=0.32, and

  • ACME: 0.25 (-0.57, 1.06), p=0.53, mediating 36.6% (-95.5%, 197.0%), p=0.53 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.18 ±0.09, p=3e-62, and
    • effect of MCPH1-D on tone: -0.12 ±0.17, p=0.5.
Restricted sampling
***Figure 111.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM* and *MCPH1*; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (dotted), 0.05 (solid) and 0.10 (dashed)._

Figure 111. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM and MCPH1; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (dotted), 0.05 (solid) and 0.10 (dashed).

For ASPM-D:

  • TE: mean = 1.3, median = 1.3; 59.2% significant at α-level 0.05 and 72.5% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 79.3, p = 0;

  • ADE: mean = 0.73, median = 0.74; 19.4% significant at α-level 0.05 and 33.9% significant at α-level 0.10; 97.4% > 0.0; one-sample one-sided t-test vs 0: t(999) = 58.4, p = 0;

  • ACME: mean = 0.54, median = 0.5; 21.5% significant at α-level 0.05 and 44.6% significant at α-level 0.10; 98.4% > 0.0; one-sample one-sided t-test vs 0: t(999) = 53.7, p = 2.6e-297;

  • β(Africa → allele): mean = -0.89, median = -0.9; 87.0% significant at α-level 0.05 and 98.9% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -237.7, p = 0;

  • β(allele → tone | Africa): mean = -0.38, median = -0.36; 34.1% significant at α-level 0.05 and 51.0% significant at α-level 0.10; 98.2% < 0.0; one-sample one-sided t-test vs 0: t(999) = -66.8, p = 0.

For MCPH1-D:

  • TE: mean = 1.1, median = 1.1; 57.6% significant at α-level 0.05 and 70.0% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 83.9, p = 0;

  • ADE: mean = 3.9, median = 2; 16.4% significant at α-level 0.05 and 26.1% significant at α-level 0.10; 83.2% > 0.0; one-sample one-sided t-test vs 0: t(999) = 17.2, p = 1.3e-58;

  • ACME: mean = -2.8, median = -0.89; 5.2% significant at α-level 0.05 and 11.9% significant at α-level 0.10; 35.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = -12.3, p = 1;

  • β(Africa → allele): mean = -2.4, median = -2.4; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -915.3, p = 0;

  • β(allele → tone | Africa): mean = 0.13, median = 0.1; 5.7% significant at α-level 0.05 and 11.9% significant at α-level 0.10; 40.4% < 0.0; one-sample one-sided t-test vs 0: t(999) = 10.3, p = 1.

Given the low sample size N = 35 unique families, relatively few effect sizes are big enough to be significant; however, there are many more significant indirect effects (ACME) for ASPM-D than for MCPH1-D: 34.1% vs 5.7% (6.0 times) for α-level 0.05, and 51.0% vs 11.9% (4.3 times) for α-level 0.10.

brms

Figure 112. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 113. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 114. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

Please note that path analysis uses a linear model (so not a Poisson one) for the tone counts; also I only use the numeric coding for Africa.

All data

Coding Africa numerically, the model fits the data very well (χ2(1)=0.29, p=0.59; CFI=1.00, TLI=1.01, NNFI=1.01 and RFI=1.00):

Figure 115. Path analysis model with standardised coefficients and significance stars. Here, macroarea (Africa vs non-Africa) is coded as numeric binary (Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D..

## lavaan 0.6-8 ended normally after 28 iterations
## 
##   Estimator                                         ML
##   Optimization method                           NLMINB
##   Number of model parameters                         8
##                                                       
##   Number of observations                           184
##                                                       
## Model Test User Model:
##                                                       
##   Test statistic                                 0.292
##   Degrees of freedom                                 1
##   P-value (Chi-square)                           0.589
## 
## Model Test Baseline Model:
## 
##   Test statistic                               369.194
##   Degrees of freedom                                 6
##   P-value                                        0.000
## 
## User Model versus Baseline Model:
## 
##   Comparative Fit Index (CFI)                    1.000
##   Tucker-Lewis Index (TLI)                       1.012
## 
## Loglikelihood and Information Criteria:
## 
##   Loglikelihood user model (H0)               -663.138
##   Loglikelihood unrestricted model (H1)       -662.992
##                                                       
##   Akaike (AIC)                                1342.276
##   Bayesian (BIC)                              1367.995
##   Sample-size adjusted Bayesian (BIC)         1342.657
## 
## Root Mean Square Error of Approximation:
## 
##   RMSEA                                          0.000
##   90 Percent confidence interval - lower         0.000
##   90 Percent confidence interval - upper         0.159
##   P-value RMSEA <= 0.05                          0.666
## 
## Standardized Root Mean Square Residual:
## 
##   SRMR                                           0.005
## 
## Parameter Estimates:
## 
##   Standard errors                           Robust.sem
##   Information                                 Expected
##   Information saturated (h1) model          Structured
## 
## Regressions:
##                    Estimate  Std.Err  z-value  P(>|z|) ci.lower ci.upper
##   n_tones ~                                                             
##     Africa_num       -0.265    0.601   -0.441    0.659   -1.443    0.913
##     ASPM_z           -0.490    0.114   -4.291    0.000   -0.713   -0.266
##     MCPH1_z          -0.131    0.229   -0.571    0.568   -0.580    0.319
##   ASPM_z ~                                                              
##     Africa_num       -1.338    0.099  -13.477    0.000   -1.533   -1.144
##   MCPH1_z ~                                                             
##     Africa_num       -2.180    0.071  -30.517    0.000   -2.320   -2.040
##    Std.lv  Std.all
##                   
##    -0.265   -0.075
##    -0.490   -0.342
##    -0.131   -0.091
##                   
##    -1.338   -0.543
##                   
##    -2.180   -0.885
## 
## Variances:
##                    Estimate  Std.Err  z-value  P(>|z|) ci.lower ci.upper
##    .n_tones           1.790    0.273    6.566    0.000    1.256    2.324
##    .ASPM_z            0.701    0.071    9.837    0.000    0.561    0.841
##    .MCPH1_z           0.216    0.036    5.943    0.000    0.145    0.287
##    Std.lv  Std.all
##     1.790    0.879
##     0.701    0.705
##     0.216    0.217
## 
## R-Square:
##                    Estimate
##     n_tones           0.121
##     ASPM_z            0.295
##     MCPH1_z           0.783
Restricted sampling
***Figure 116.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 116. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

It can be seen that:

  • the models fits:

    • 97.9% of the p-values are not significant
    • mean(CFI) = 0.99, median(CFI) = 1, sd(CFI) = 0.01, IQR(CFI) = 0.01
    • mean(TLI) = 0.99, median(TLI) = 1.01, sd(TLI) = 0.09, IQR(TLI) = 0.15
    • mean(NNFI) = 0.99, median(NNFI) = 1.01, sd(NNFI) = 0.09, IQR(NNFI) = 0.15
    • mean(RFI) = 0.91, median(RFI) = 0.93, sd(RFI) = 0.08, IQR(RFI) = 0.13
  • Africa → ASPM-D: mean = -0.88, median = -0.89, sd = 0.12, IQR = 0.16, 100.0% < 0; 99.9% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -2.3e+02, p = 0

  • Africa → MCPH1-D: mean = -2.4, median = -2.4, sd = 0.083, IQR = 0.12, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -9.1e+02, p = 0

  • Africa → tone counts: mean = 0.77, median = 0.83, sd = 1.1, IQR = 1.6, 74.9% > 0; 10.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 22, p = 2e-86

  • ASPM-D → tone counts: mean = -0.32, median = -0.31, sd = 0.16, IQR = 0.22, 98.7% < 0; 22.5% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -63, p = 0

  • MCPH1-D → tone counts: mean = 0.019, median = 0.034, as = 0.45, IQR = 0.65, 47.4% < 0; 3.3% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 1.3, p = 0.91

Unrounded (raw) imputed counts

I kept only the entries with non-missing data for the tone counts, ASPM-D and MCPH1-D, and if there are more than one possible languages or allele frequencies for a given sample, I only kept those entries that have different tone or allele data. The resulting dataset has 200 observations, distributed among 136 unique Glottolg codes in 37 families (ranging from a minimum of 1 language per family to a maximum of 51, with a mean 5.4 and median 2 languages per family) and 4 macroareas.

***Figure 117.*** _Distribution of tone *counts* (unrounded)._

Figure 117. Distribution of tone counts (unrounded).

***Figure 118.*** _Distribution of tone *counts* (unrounded) across the world._

Figure 118. Distribution of tone counts (unrounded) across the world.

***Figure 119.*** _Relationship between tone *counts* (unrounded; colors) and the two alleles (frequency) by macroarea._

Figure 119. Relationship between tone counts (unrounded; colors) and the two alleles (frequency) by macroarea.

Power analysis

I use simulations for power analysis (as implemented by package simr), focusing on the effect of ASPM-D on tone1 using glmer, i.e. logistic regression with ASPM-D as fixed effect and controlling for language family (as random effect) and macroarea as fixed effect.

Observed power

The observed effect size of ASPM-D is βASPM-D = -0.4, pASPM-D = 0.41, with an ICC = 68.4% on 35 level-2 groups (families) and 181 observations (languages/samples). The observed (post-hoc) power 1 - β = %, 95%CI = .

Changing the number of languages

If we keep the families but change the number of languages per family:

***Figure 120.*** _Estimated power (with 95%) when changing the number of languages but keeping everything else constant._

Figure 120. Estimated power (with 95%) when changing the number of languages but keeping everything else constant.

Changing the number of families

If we change the number of families:

***Figure 121.*** _Estimated power (with 95%) when changing the number of language families but keeping everything else constant._

Figure 121. Estimated power (with 95%) when changing the number of language families but keeping everything else constant.

Changing the number of families and languages

If we change the number of families and the number of languages per family:

***Figure 122.*** _Estimated power when changing the number of language families and the number of languages per family, but keeping everything else constant. Color is proportional to power and the shape shows if the power is > 80%. The two vertical dotted lines are the approximate number of families in Ethnologue (blue, ~150) and Glottolog (black, ~420). The horizontal dotted lines are summaries of the number of languages in Glottolog: the mean (red, ~20), the median (black, 2) and the median excluding isolates (blue, 5); not shown is the maxmimum (~1400 in Atlantic-Congo)._

Figure 122. Estimated power when changing the number of language families and the number of languages per family, but keeping everything else constant. Color is proportional to power and the shape shows if the power is > 80%. The two vertical dotted lines are the approximate number of families in Ethnologue (blue, ~150) and Glottolog (black, ~420). The horizontal dotted lines are summaries of the number of languages in Glottolog: the mean (red, ~20), the median (black, 2) and the median excluding isolates (blue, 5); not shown is the maxmimum (~1400 in Atlantic-Congo).

Appendix I: Gaussian Process

Here I model language contact with a 2D Gaussian Process as suggested in, for example, McElreath (2020), using brms’s gp(). tone is regressed on ASPM-D and MCPH1-D with language family and (meta)population as (nested) random effects, and a 2D Gaussian process separately for each macroarea.

tone1

  • ASPM only:
    • β = -0.88, 89%HDI = [-1.63, -0.06]
    • posterior probability p(β<0) = 0.96 (evidence ratio = 25), p(β=0) = 0.59 (evidence ratio = 1.4)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 3.5%; pROPE = 0.065
    • comparison ‘null’ vs ‘ASPM’: [B= L= W=(33%:67%) K=]: anecdotal evidence for null against ASPM (BF=1.3), LOO=-0.05 [SE=2.69], WAIC=-0.69 [SE=2.74], KFOLD=-1.21 [SE=3.41]
  • MCPH1 only:
    • β = -1.03, 89%HDI = [-1.63, -0.45]
    • posterior probability p(β<0) = 0.99 (evidence ratio = 1.7e+02), p(β=0) = 0.15 (evidence ratio = 0.17)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 0%; pROPE = 0.011
    • comparison ‘null’ vs ‘MCPH1’: [B< L< W<(10%:90%) K=]: moderate evidence for MCPH1 against null (BF=0.301), LOO=-2.13 [SE=1.73], WAIC=-2.22 [SE=1.73], KFOLD=-2.02 [SE=2.70]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B= L= W=(9%:91%) K=]: anecdotal evidence for both against null (BF=0.704), LOO=-1.87 [SE=2.93], WAIC=-2.34 [SE=2.95], KFOLD=-2.34 [SE=3.50]
    • interaction:
      • posterior probability p(=0) = 0.87 (evidence ratio = 6.6)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 31.5%; pROPE = 0.28
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L>> W>(76%:24%) K>]: moderate evidence for no interaction against with interaction (BF=5.75), LOO=1.49 [SE=0.73], WAIC=1.16 [SE=0.66], KFOLD=2.70 [SE=2.09]
    • ASPM (partial):
      • β = -0.58, 89%HDI = [-1.35, 0.20]
      • posterior probability p(β<0) = 0.88 (evidence ratio = 7.4), p(β=0) = 0.76 (evidence ratio = 3.2)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 15.7%; pROPE = 0.14
    • MCPH1 (partial):
      • β = -0.85, 89%HDI = [-1.47, -0.25]
      • posterior probability p(β<0) = 0.99 (evidence ratio = 77), p(β=0) = 0.41 (evidence ratio = 0.69)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 0%; pROPE = 0.032
***Figure 123.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see._***Figure 123.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see._

Figure 123. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see.

***Figure 124.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 124.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 124. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 125.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 125.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 125. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 126.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 126.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 126. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

tone2

  • ASPM only:
    • β = -1.15, 89%HDI = [-2.12, -0.16]
    • posterior probability p(β<0) = 0.97 (evidence ratio = 33), p(β=0) = 0.5 (evidence ratio = 1)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 0.6%; pROPE = 0.044
    • comparison ‘null’ vs ‘ASPM’: [B= L= W=(41%:59%) K=]: anecdotal evidence for ASPM against null (BF=0.767), LOO=-0.34 [SE=1.58], WAIC=-0.34 [SE=1.59], KFOLD=-0.07 [SE=1.64]
  • MCPH1 only:
    • β = -0.63, 89%HDI = [-1.27, -0.04]
    • posterior probability p(β<0) = 0.95 (evidence ratio = 19), p(β=0) = 0.68 (evidence ratio = 2.1)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 6.5%; pROPE = 0.099
    • comparison ‘null’ vs ‘MCPH1’: [B= L= W=(55%:45%) K=]: anecdotal evidence for null against MCPH1 (BF=2.14), LOO=0.06 [SE=1.58], WAIC=0.19 [SE=1.58], KFOLD=0.88 [SE=1.88]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B> L= W=(45%:55%) K=]: moderate evidence for null against both (BF=4.38), LOO=-0.23 [SE=1.82], WAIC=-0.19 [SE=1.81], KFOLD=0.17 [SE=1.92]
    • interaction:
      • posterior probability p(=0) = 0.83 (evidence ratio = 4.7)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 22.4%; pROPE = 0.2
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L> W>(62%:38%) K>>]: moderate evidence for no interaction against with interaction (BF=6.35), LOO=0.53 [SE=0.37], WAIC=0.48 [SE=0.37], KFOLD=2.63 [SE=1.03]
    • ASPM (partial):
      • β = -0.88, 89%HDI = [-1.96, 0.15]
      • posterior probability p(β<0) = 0.91 (evidence ratio = 10), p(β=0) = 0.68 (evidence ratio = 2.1)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 9.9%; pROPE = 0.092
    • MCPH1 (partial):
      • β = -0.42, 89%HDI = [-1.04, 0.21]
      • posterior probability p(β<0) = 0.86 (evidence ratio = 6.3), p(β=0) = 0.83 (evidence ratio = 4.7)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 24.1%; pROPE = 0.214
***Figure 127.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see._***Figure 127.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see._

Figure 127. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see.

***Figure 128.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 128.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 128. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 129.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 129.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 129. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 130.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 130.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 130. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Tone counts

  • ASPM only:
    • β = -0.22, 89%HDI = [-0.66, 0.24]
    • posterior probability p(β<0) = 0.78 (evidence ratio = 3.5), p(β=0) = 0.9 (evidence ratio = 8.9)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 23.7%; pROPE = 0.211
    • comparison ‘null’ vs ‘ASPM’: [B> L>> W>>(90%:10%) K=]: moderate evidence for null against ASPM (BF=9.37), LOO=2.40 [SE=1.07], WAIC=2.20 [SE=1.01], KFOLD=1.54 [SE=1.62]
  • MCPH1 only:
    • β = -0.41, 89%HDI = [-0.77, -0.08]
    • posterior probability p(β<0) = 0.95 (evidence ratio = 21), p(β=0) = 0.7 (evidence ratio = 2.3)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 1.2%; pROPE = 0.058
    • comparison ‘null’ vs ‘MCPH1’: [B> L> W>(93%:7%) K=]: moderate evidence for null against MCPH1 (BF=3.35), LOO=2.30 [SE=1.36], WAIC=2.53 [SE=1.30], KFOLD=1.72 [SE=1.79]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L> W>(97%:3%) K>]: strong evidence for null against both (BF=14), LOO=3.61 [SE=2.03], WAIC=3.47 [SE=1.89], KFOLD=3.27 [SE=2.59]
    • interaction:
      • posterior probability p(=0) = 0.93 (evidence ratio = 12)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 33.7%; pROPE = 0.3
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L>> W>>(68%:32%) K>>]: moderate evidence for no interaction against with interaction (BF=6.73), LOO=1.03 [SE=0.44], WAIC=0.74 [SE=0.37], KFOLD=4.04 [SE=1.72]
    • ASPM (partial):
      • β = -0.27, 89%HDI = [-0.67, 0.17]
      • posterior probability p(β<0) = 0.84 (evidence ratio = 5.4), p(β=0) = 0.88 (evidence ratio = 7.5)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 19.5%; pROPE = 0.174
    • MCPH1 (partial):
      • β = -0.4, 89%HDI = [-0.72, -0.11]
      • posterior probability p(β<0) = 0.97 (evidence ratio = 29), p(β=0) = 0.67 (evidence ratio = 2)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 0%; pROPE = 0.049
***Figure 131.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see._***Figure 131.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see._

Figure 131. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right). Please note that I have cut the x-axis at 2.5 as the distributions of the sdgp and lscale have a few extreme outliers which would make the plots impossible to see.

***Figure 132.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 132.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 132. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 133.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 133.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 133. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

Appendix II: Sensitivity to the prior

Here I explore the sensitivity to the prior of the brms models, focusing on each “derived” allele independently.

tone1

ASPM-D

All models show good mixing and convergence (not shown).

Comparing the posterior distribution for ASPM-D frequency (z-scored) for various prior distributions. The HDI is a 89%HDI; p(β<0) and p(β=0) show the posterior probability (and the evidence ratio, in parantheses); the ROPE is [-0.18, 0.18].
Prior name Prior distribution β HDI p(β<0) p(β=0) %HDI in ROPE pROPE
default student_t(3, 0, 3) -0.70 [-1.52, 0.33] 0.89 (8.0) 0.73 (2.7) 13.3% 0.12
flat normal(0, 10) -0.74 [-1.63, 0.24] 0.9 (9.0) 0.89 (8.0) 13.1% 0.12
default_normal normal(0, 5) -0.70 [-1.60, 0.24] 0.89 (8.5) 0.8 (4.0) 13.8% 0.12
narrow_0 student_t(3, 0, 1) -0.55 [-1.32, 0.23] 0.87 (7.0) 0.55 (1.2) 18.7% 0.17
verynarrow_0 student_t(3, 0, 0.1) -0.05 [-0.28, 0.16] 0.62 (1.6) 0.49 (1.0) 91.1% 0.82
negative_default student_t(3, -1, 3) -0.75 [-1.71, 0.13] 0.91 (10.0) 0.73 (2.7) 11.4% 0.11
negative_narrow student_t(3, -1, 1) -0.82 [-1.60, -0.06] 0.96 (25.1) 0.47 (0.9) 4.0% 0.07
verynegative_default student_t(3, -3, 3) -0.87 [-1.83, 0.10] 0.94 (14.5) 0.79 (3.7) 8.3% 0.08
verynegative_narrow student_t(3, -3, 1) -1.33 [-2.44, -0.21] 0.98 (51.6) 0.8 (3.9) 0.0% 0.03
positive_default student_t(3, 1, 3) -0.62 [-1.52, 0.28] 0.87 (6.8) 0.76 (3.2) 14.0% 0.12
positive_narrow student_t(3, 1, 1) -0.34 [-1.13, 0.52] 0.74 (2.9) 0.74 (2.9) 25.7% 0.23
verypositive_default student_t(3, 3, 3) -0.55 [-1.39, 0.44] 0.84 (5.2) 0.86 (6.4) 17.8% 0.16
verypositive_narrow student_t(3, 3, 1) -0.23 [-1.12, 0.78] 0.66 (1.9) 0.97 (27.8) 25.0% 0.22
informative student_t(3, -0.7, 3) -0.72 [-1.64, 0.21] 0.9 (9.2) 0.73 (2.7) 13.0% 0.12

MCPH1-D

All models show good mixing and convergence (not shown).

Comparing the posterior distribution for MCPH1-D frequency (z-scored) for various prior distributions. The HDI is a 89%HDI; p(β<0) and p(β=0) show the posterior probability (and the evidence ratio, in parantheses); the ROPE is [-0.18, 0.18].
Prior name Prior distribution β HDI p(β<0) p(β=0) %HDI in ROPE pROPE
default student_t(3, 0, 3) -0.65 [-1.69, 0.47] 0.84 (5.2) 0.75 (3.0) 14.3% 0.13
flat normal(0, 10) -0.68 [-1.76, 0.48] 0.85 (5.5) 0.9 (8.6) 13.6% 0.12
default_normal normal(0, 5) -0.67 [-1.76, 0.47] 0.84 (5.1) 0.83 (4.8) 14.9% 0.13
narrow_0 student_t(3, 0, 1) -0.49 [-1.35, 0.46] 0.82 (4.4) 0.56 (1.3) 18.6% 0.17
verynarrow_0 student_t(3, 0, 0.1) -0.04 [-0.25, 0.17] 0.59 (1.4) 0.52 (1.1) 94.0% 0.84
negative_default student_t(3, -1, 3) -0.73 [-1.79, 0.35] 0.87 (6.6) 0.75 (3.0) 12.6% 0.11
negative_narrow student_t(3, -1, 1) -0.80 [-1.74, 0.03] 0.93 (12.7) 0.57 (1.3) 7.5% 0.09
verynegative_default student_t(3, -3, 3) -0.85 [-1.93, 0.27] 0.9 (8.7) 0.8 (3.9) 11.5% 0.10
verynegative_narrow student_t(3, -3, 1) -1.31 [-2.51, -0.09] 0.97 (27.8) 0.84 (5.3) 2.1% 0.04
positive_default student_t(3, 1, 3) -0.61 [-1.64, 0.52] 0.81 (4.3) 0.77 (3.3) 15.6% 0.14
positive_narrow student_t(3, 1, 1) -0.22 [-1.26, 0.80] 0.63 (1.7) 0.75 (2.9) 23.6% 0.21
verypositive_default student_t(3, 3, 3) -0.47 [-1.56, 0.59] 0.77 (3.3) 0.87 (6.4) 18.1% 0.16
verypositive_narrow student_t(3, 3, 1) -0.06 [-1.39, 1.16] 0.55 (1.2) 0.96 (22.6) 19.9% 0.18
informative student_t(3, -0.6, 3) -0.66 [-1.83, 0.42] 0.83 (4.9) 0.74 (2.8) 13.0% 0.12

tone2

ASPM-D

All models show good mixing and convergence (not shown).

Comparing the posterior distribution for ASPM-D frequency (z-scored) for various prior distributions. The HDI is a 89%HDI; p(β<0) and p(β=0) show the posterior probability (and the evidence ratio, in parantheses); the ROPE is [-0.18, 0.18].
Prior name Prior distribution β HDI p(β<0) p(β=0) %HDI in ROPE pROPE
default student_t(3, 0, 3) -1.30 [-2.72, 0.17] 0.93 (13.7) 0.56 (1.3) 6.3% 0.06
flat normal(0, 10) -1.76 [-3.44, 0.22] 0.95 (20.4) 0.71 (2.5) 3.8% 0.03
default_normal normal(0, 5) -1.50 [-3.04, 0.22] 0.94 (17.0) 0.63 (1.7) 5.3% 0.05
narrow_0 student_t(3, 0, 1) -0.67 [-1.73, 0.40] 0.84 (5.4) 0.52 (1.1) 15.6% 0.14
verynarrow_0 student_t(3, 0, 0.1) -0.03 [-0.23, 0.20] 0.55 (1.2) 0.5 (1.0) 94.4% 0.84
negative_default student_t(3, -1, 3) -1.42 [-2.85, 0.07] 0.95 (17.7) 0.55 (1.2) 4.9% 0.05
negative_narrow student_t(3, -1, 1) -1.05 [-1.98, 0.02] 0.96 (23.1) 0.44 (0.8) 4.3% 0.06
verynegative_default student_t(3, -3, 3) -1.76 [-3.33, -0.17] 0.98 (40.2) 0.54 (1.2) 0.2% 0.03
verynegative_narrow student_t(3, -3, 1) -1.89 [-3.12, -0.61] 0.99 (120.2) 0.57 (1.4) 0.0% 0.01
positive_default student_t(3, 1, 3) -1.21 [-2.58, 0.36] 0.91 (10.1) 0.64 (1.8) 7.9% 0.07
positive_narrow student_t(3, 1, 1) -0.45 [-1.81, 0.77] 0.7 (2.3) 0.7 (2.3) 19.6% 0.17
verypositive_default student_t(3, 3, 3) -1.14 [-2.60, 0.44] 0.89 (7.8) 0.77 (3.3) 9.1% 0.08
verypositive_narrow student_t(3, 3, 1) -0.40 [-1.94, 1.51] 0.68 (2.1) 0.94 (16.3) 14.2% 0.13
informative student_t(3, -1.3, 3) -1.48 [-2.94, 0.10] 0.95 (20.5) 0.53 (1.1) 3.9% 0.04

MCPH1-D

All models show good mixing and convergence (not shown).

Comparing the posterior distribution for MCPH1-D frequency (z-scored) for various prior distributions. The HDI is a 89%HDI; p(β<0) and p(β=0) show the posterior probability (and the evidence ratio, in parantheses); the ROPE is [-0.18, 0.18].
Prior name Prior distribution β HDI p(β<0) p(β=0) %HDI in ROPE pROPE
default student_t(3, 0, 3) -0.93 [-2.41, 0.53] 0.85 (5.6) 0.68 (2.2) 10.6% 0.09
flat normal(0, 10) -1.23 [-3.11, 0.51] 0.88 (7.0) 0.83 (5.0) 8.2% 0.07
default_normal normal(0, 5) -1.07 [-2.60, 0.66] 0.86 (6.2) 0.75 (2.9) 9.2% 0.08
narrow_0 student_t(3, 0, 1) -0.47 [-1.61, 0.68] 0.75 (3.0) 0.57 (1.3) 18.7% 0.17
verynarrow_0 student_t(3, 0, 0.1) -0.01 [-0.25, 0.19] 0.53 (1.1) 0.5 (1.0) 93.8% 0.84
negative_default student_t(3, -1, 3) -1.05 [-2.58, 0.45] 0.88 (7.0) 0.66 (2.0) 8.8% 0.08
negative_narrow student_t(3, -1, 1) -0.89 [-1.98, 0.15] 0.92 (10.9) 0.5 (1.0) 8.1% 0.07
verynegative_default student_t(3, -3, 3) -1.31 [-2.88, 0.30] 0.92 (10.8) 0.73 (2.7) 6.7% 0.06
verynegative_narrow student_t(3, -3, 1) -1.73 [-3.11, -0.32] 0.98 (39.4) 0.75 (2.9) 0.0% 0.02
positive_default student_t(3, 1, 3) -0.81 [-2.25, 0.84] 0.81 (4.4) 0.72 (2.6) 12.2% 0.11
positive_narrow student_t(3, 1, 1) -0.08 [-1.36, 1.31] 0.53 (1.1) 0.69 (2.2) 19.5% 0.17
verypositive_default student_t(3, 3, 3) -0.67 [-2.30, 0.85] 0.77 (3.4) 0.82 (4.5) 13.8% 0.12
verypositive_narrow student_t(3, 3, 1) 0.40 [-1.51, 2.62] 0.42 (0.7) 0.94 (14.7) 11.8% 0.10
informative student_t(3, -0.9, 3) -1.01 [-2.44, 0.46] 0.88 (7.5) 0.69 (2.2) 10.1% 0.09

Tone counts

ASPM-D

All models show good mixing and convergence (not shown).

Comparing the posterior distribution for ASPM-D frequency (z-scored) for various prior distributions. The HDI is a 89%HDI; p(β<0) and p(β=0) show the posterior probability (and the evidence ratio, in parantheses); the ROPE is [-0.10, 0.10].
Prior name Prior distribution β HDI p(β<0) p(β=0) %HDI in ROPE pROPE
default student_t(3, 0, 3) -0.24 [-0.65, 0.16] 0.82 (4.7) 0.89 (8.1) 22.2% 0.20
flat normal(0, 10) -0.25 [-0.67, 0.16] 0.83 (5.0) 0.96 (23.4) 21.1% 0.19
default_normal normal(0, 5) -0.24 [-0.66, 0.16] 0.82 (4.7) 0.92 (12.1) 21.8% 0.19
narrow_0 student_t(3, 0, 1) -0.22 [-0.63, 0.18] 0.81 (4.4) 0.75 (2.9) 23.4% 0.21
verynarrow_0 student_t(3, 0, 0.1) -0.04 [-0.22, 0.14] 0.63 (1.7) 0.53 (1.1) 72.9% 0.65
negative_default student_t(3, -1, 3) -0.26 [-0.69, 0.15] 0.83 (5.0) 0.9 (8.5) 21.6% 0.19
negative_narrow student_t(3, -1, 1) -0.32 [-0.74, 0.07] 0.9 (8.9) 0.76 (3.2) 14.3% 0.14
verynegative_default student_t(3, -3, 3) -0.28 [-0.69, 0.14] 0.86 (6.2) 0.93 (12.3) 18.6% 0.17
verynegative_narrow student_t(3, -3, 1) -0.34 [-0.77, 0.09] 0.89 (8.4) 0.96 (27.0) 14.3% 0.13
positive_default student_t(3, 1, 3) -0.23 [-0.67, 0.16] 0.82 (4.6) 0.9 (9.1) 22.4% 0.20
positive_narrow student_t(3, 1, 1) -0.15 [-0.55, 0.27] 0.72 (2.6) 0.87 (6.5) 28.6% 0.25
verypositive_default student_t(3, 3, 3) -0.22 [-0.62, 0.21] 0.79 (3.9) 0.94 (15.3) 23.0% 0.20
verypositive_narrow student_t(3, 3, 1) -0.14 [-0.57, 0.27] 0.7 (2.3) 0.98 (58.0) 30.0% 0.27
informative student_t(3, -0.2, 3) -0.26 [-0.66, 0.14] 0.85 (5.6) 0.89 (7.8) 20.2% 0.18

MCPH1-D

All models show good mixing and convergence (not shown).

Comparing the posterior distribution for MCPH1-D frequency (z-scored) for various prior distributions. The HDI is a 89%HDI; p(β<0) and p(β=0) show the posterior probability (and the evidence ratio, in parantheses); the ROPE is [-0.10, 0.10].
Prior name Prior distribution β HDI p(β<0) p(β=0) %HDI in ROPE pROPE
default student_t(3, 0, 3) -0.23 [-0.70, 0.20] 0.79 (3.7) 0.89 (7.9) 21.8% 0.19
flat normal(0, 10) -0.24 [-0.66, 0.24] 0.81 (4.3) 0.96 (22.7) 20.4% 0.18
default_normal normal(0, 5) -0.24 [-0.68, 0.24] 0.8 (4.0) 0.92 (11.4) 19.6% 0.17
narrow_0 student_t(3, 0, 1) -0.21 [-0.65, 0.21] 0.79 (3.7) 0.72 (2.6) 21.9% 0.20
verynarrow_0 student_t(3, 0, 0.1) -0.04 [-0.22, 0.16] 0.62 (1.6) 0.53 (1.1) 70.3% 0.63
negative_default student_t(3, -1, 3) -0.24 [-0.69, 0.22] 0.81 (4.3) 0.89 (7.8) 19.5% 0.17
negative_narrow student_t(3, -1, 1) -0.30 [-0.73, 0.11] 0.87 (6.8) 0.79 (3.8) 16.6% 0.15
verynegative_default student_t(3, -3, 3) -0.25 [-0.71, 0.19] 0.81 (4.4) 0.93 (12.7) 20.2% 0.18
verynegative_narrow student_t(3, -3, 1) -0.31 [-0.77, 0.14] 0.86 (5.9) 0.97 (31.5) 15.4% 0.14
positive_default student_t(3, 1, 3) -0.22 [-0.66, 0.23] 0.79 (3.8) 0.9 (8.8) 21.3% 0.19
positive_narrow student_t(3, 1, 1) -0.13 [-0.59, 0.32] 0.67 (2.1) 0.85 (5.6) 27.5% 0.24
verypositive_default student_t(3, 3, 3) -0.20 [-0.65, 0.25] 0.77 (3.3) 0.93 (13.8) 22.3% 0.20
verypositive_narrow student_t(3, 3, 1) -0.12 [-0.59, 0.37] 0.66 (1.9) 0.98 (52.4) 25.9% 0.23
informative student_t(3, -0.2, 3) -0.24 [-0.71, 0.17] 0.82 (4.5) 0.89 (7.9) 20.6% 0.18

Appendix III: Excluding the “proxy” SNPs

Here I conduct some of the analyses using only the actual “derived” loci for the two genes (i.e., excluding all the “proxy” SNPs used in the full analysis).

tone1

There are 108 observations, distributed among 75 unique Glottolg codes in 29 families (ranging from a minimum of 1 language per family to a maximum of 38, with a mean 3.7 and median 2 languages per family) and 4 macroareas.

There are 98:83:75 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 6 53 2 3 64
Yes 19 21 3 1 44
Sum 25 74 5 4 108
***Figure 134.*** _Distribution of *tone1*._

Figure 134. Distribution of tone1.

***Figure 135.*** _Map of *tone1*._

Figure 135. Map of tone1.

***Figure 136.*** _Relationship between *tone1*, *ASPM*-D and *MCPH1*-D._

Figure 136. Relationship between tone1, ASPM-D and MCPH1-D.

Regressions

glmer

All data
  • null model: R2 = 0.0%, ICC = 53.2%
  • macroarea: pmacroarea/null = 0.046
  • ASPM:
    • by itself: R2 = 6.8%, β = -0.68 ± 0.38, pASPM/null = 0.065
    • quadratic: R2 = 7.0%, βASPM2 = -0.61 ± 0.43, pASPM2/ASPM = 0.71
    • with macroarea: R2 = 18.2%, pmacroarea/ASPM = 0.19, pASPM/macroarea = 0.64
  • MCPH1:
    • by itself: R2 = 8.5%, β = -0.79 ± 0.40, pMCPH1/null = 0.042
    • quadratic: R2 = 9.5%, βMCPH12 = -0.74 ± 0.39, pMCPH12/MCPH1 = 0.28
    • with macroarea: R2 = 18.2%, pmacroarea/MCPH1 = 0.26, pMCPH1/macroarea = 0.68
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 11.0%, βASPM = -0.45 ± 0.40, pASPM/MCPH1 = 0.26, βMCPH1 = -0.57 ± 0.42, pMCPH1/ASPM = 0.16, pASPM+MCPH1/null = 0.068,
    • interaction: R2 = 11.4%, pASPM:MCPH1/ASPM+MCPH1 = 0.62
Alleles on macroarea

To better understand this overlap between family, macroarea and the two “derived” alleles, I regressed (separately) the ASPM-D and MCPH1-D on the macroarea, using mixed-effects beta regression (after replacing all \(0.0\) values by \(10^{-7}\) and all \(1.0\) by \(1.0-10^{-7}\), respectively) with language family as random effect:

  • the alleles are very strongly clustered within families:
    • ASPM: ICC = 100.0%
    • MCPH1: ICC = 100.0%
  • macroarea predicts their distribution very strongly:
    • ASPM: p = 3.3e-05, R2 = 39.1%
    • MCPH1: p = 2.3e-09, R2 = 74.1%
  • separating Africa vs the rest of the world seems to drive most of this effect (both alleles have lower frequencies in Africa):
    • ASPM: p = 8.1e-05, R2 = 24.1%
    • MCPH1: p = 1.5e-07, R2 = 49.5%
Randomization

I performed 1000 independent replications of each of these parameter combinations, and below are the distributions of the permuted values versus the original ones (i.e., those obtained on the original, non-permuted data).

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 5% 4% 3% 5% 1%
unrestricted none alleles-together 8% 6% 6% 9% 6% 5%
unrestricted none alleles-independent 8% 5% 6% 9% 5% 2%
unrestricted fixef tone 0% 7% 7% 29% 5% 33%
unrestricted fixef alleles-together 89% 6% 6% 34% 6% 28%
unrestricted fixef alleles-independent 86% 5% 5% 30% 5% 28%
macroareas none tone 0% 82% 14% 19% 71% 51%
macroareas none alleles-together 39% 30% 8% 27% 22% 56%
macroareas none alleles-independent 43% 35% 12% 34% 25% 59%
macroareas fixef tone 0% 5% 4% 26% 5% 33%
macroareas fixef alleles-together 86% 5% 5% 32% 5% 38%
macroareas fixef alleles-independent 86% 4% 5% 36% 4% 38%
families none tone 20% 13% 2% 10% 17% 46%
families none alleles-together 9% 6% 2% 16% 4% 21%
families none alleles-independent 13% 9% 7% 25% 8% 26%
families fixef tone 20% 6% 2% 33% 7% 65%
families fixef alleles-together 79% 1% 2% 35% 1% 19%
families fixef alleles-independent 84% 2% 3% 32% 1% 19%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 137.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 98.2% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -56.0, mean = -0.55, *p* = 1.2e-310), 56.3%, when controlling for the macroarea (*t*(999) = -7.6, mean = -0.10, *p* = 4e-14), and 54.3% when controlling for both macroarea and *MCPH1* (*t*(999) = -7.3, mean = -0.10, *p* = 2.2e-13). For *MCPH1*-D (right): 100% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -88.1, mean = -0.54, *p* = 0), 58.4% when controlling for the macroarea (*t*(999) = -7.1, mean = -0.15, *p* = 9.9e-13), and 60% when controlling for both macroarea and *ASPM* (*t*(999) = -8.8, mean = -0.19, *p* = 3.8e-18)._

Figure 137. Results for 1000 restricted samplings. For ASPM-D (left): 98.2% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -56.0, mean = -0.55, p = 1.2e-310), 56.3%, when controlling for the macroarea (t(999) = -7.6, mean = -0.10, p = 4e-14), and 54.3% when controlling for both macroarea and MCPH1 (t(999) = -7.3, mean = -0.10, p = 2.2e-13). For MCPH1-D (right): 100% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -88.1, mean = -0.54, p = 0), 58.4% when controlling for the macroarea (t(999) = -7.1, mean = -0.15, p = 9.9e-13), and 60% when controlling for both macroarea and ASPM (t(999) = -8.8, mean = -0.19, p = 3.8e-18).

brms

  • ASPM only:
    • β = -0.53, 89%HDI = [-1.46, 0.31]
    • posterior probability p(β<0) = 0.83 (evidence ratio = 5), p(β=0) = 0.8 (evidence ratio = 4.1)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 18.8%; pROPE = 0.168
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(61%:39%) K>]: moderate evidence for null against ASPM (BF=3.2), LOO=0.42 [SE=1.20], WAIC=0.46 [SE=1.07], KFOLD=1.90 [SE=1.88]
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(61%:39%) K>]: moderate evidence for null against ASPM (BF=3.2), LOO=0.42 [SE=1.20], WAIC=0.46 [SE=1.07], KFOLD=1.90 [SE=1.88]
  • MCPH1 only:
    • β = -0.7, 89%HDI = [-1.91, 0.43]
    • posterior probability p(β<0) = 0.84 (evidence ratio = 5.2), p(β=0) = 0.75 (evidence ratio = 3.1)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 13.2%; pROPE = 0.117
    • comparison ‘null’ vs ‘MCPH1’: [B= L= W=(52%:48%) K>]: anecdotal evidence for null against MCPH1 (BF=2.89), LOO=0.27 [SE=0.87], WAIC=0.07 [SE=0.75], KFOLD=1.68 [SE=1.60]
    • comparison ‘null’ vs ‘MCPH1’: [B= L= W=(52%:48%) K>]: anecdotal evidence for null against MCPH1 (BF=2.89), LOO=0.27 [SE=0.87], WAIC=0.07 [SE=0.75], KFOLD=1.68 [SE=1.60]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L> W=(69%:31%) K>]: strong evidence for null against both (BF=15.6), LOO=1.80 [SE=1.38], WAIC=0.82 [SE=1.28], KFOLD=2.78 [SE=1.76]
    • interaction:
      • posterior probability p(=0) = 0.77 (evidence ratio = 3.3)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 14.9%; pROPE = 0.132
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L= W=(44%:56%) K>>]: moderate evidence for no interaction against with interaction (BF=3.55), LOO=0.25 [SE=0.82], WAIC=-0.25 [SE=0.68], KFOLD=3.69 [SE=1.62]
    • ASPM (partial):
      • β = -0.41, 89%HDI = [-1.33, 0.55]
      • posterior probability p(β<0) = 0.76 (evidence ratio = 3.1), p(β=0) = 0.82 (evidence ratio = 4.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 22.1%; pROPE = 0.197
    • MCPH1 (partial):
      • β = -0.6, 89%HDI = [-1.74, 0.63]
      • posterior probability p(β<0) = 0.8 (evidence ratio = 4), p(β=0) = 0.77 (evidence ratio = 3.3)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 15.7%; pROPE = 0.14
***Figure 138.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 138.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 138. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 139.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 139.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 139. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 140.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 140.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 140. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 141.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 141.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 141. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Mediation and path analysis

Mediation analysis

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 0.44 (0.24, 0.61), p=0, decomposed into:

  • average direct effect (ADE): 0.28 (0.04, 0.51), p=0.02, and

  • average indirect effect (ACME) mediated by ASPM-D: 0.16 (0.03, 0.30), p=0.022, mediating 35.7% (5.6%, 85.0%), p=0.022 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.22 ±0.20, p=1.2e-08, and
    • effect of ASPM-D on tone: -0.63 ±0.27, p=0.022.

For MCPH1-D:

  • TE: 0.44 (0.24, 0.61), p=0, decomposed into:

  • ADE: 0.53 (0.10, 0.73), p=0.012, and

  • ACME: -0.09 (-0.29, 0.28), p=0.43, mediating -25.9% (-104.5%, 70.5%), p=0.43 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.08 ±0.11, p=1.7e-36, and
    • effect of MCPH1-D on tone: 0.38 ±0.48, p=0.42.
Restricted sampling
***Figure 142.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM*-D and *MCPH1*-D; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted)._

Figure 142. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM-D and MCPH1-D; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted).

For ASPM-D:

  • TE: mean = 0.32, median = 0.33; 15.6% significant at α-level 0.05 and 49.1% significant at α-level 0.10; 99.9% > 0.0; one-sample one-sided t-test vs 0: t(999) = 115.5, p = 0;

  • ADE: mean = 0.28, median = 0.28; 6.4% significant at α-level 0.05 and 24.7% significant at α-level 0.10; 99.7% > 0.0; one-sample one-sided t-test vs 0: t(999) = 87.8, p = 0;

  • ACME: mean = 0.046, median = 0.044; 0.0% significant at α-level 0.05 and 1.8% significant at α-level 0.10; 79.3% > 0.0; one-sample one-sided t-test vs 0: t(999) = 30.0, p = 1.1e-141;

  • β(Africa → allele): mean = -0.82, median = -0.84; 69.4% significant at α-level 0.05 and 89.8% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -228.0, p = 0;

  • β(allele → tone | Africa): mean = -0.31, median = -0.29; 0.1% significant at α-level 0.05 and 4.3% significant at α-level 0.10; 78.7% < 0.0; one-sample one-sided t-test vs 0: t(999) = -28.3, p = 5.8e-130.

For MCPH1-D:

  • TE: mean = 0.33, median = 0.33; 15.8% significant at α-level 0.05 and 50.0% significant at α-level 0.10; 99.9% > 0.0; one-sample one-sided t-test vs 0: t(999) = 116.1, p = 0;

  • ADE: mean = 0.35, median = 0.39; 2.1% significant at α-level 0.05 and 12.3% significant at α-level 0.10; 95.6% > 0.0; one-sample one-sided t-test vs 0: t(999) = 65.5, p = 0;

  • ACME: mean = -0.029, median = -0.048; 0.1% significant at α-level 0.05 and 0.8% significant at α-level 0.10; 38.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = -6.5, p = 1;

  • β(Africa → allele): mean = -2.3, median = -2.3; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -953.8, p = 0;

  • β(allele → tone | Africa): mean = 0.34, median = 0.33; 0.2% significant at α-level 0.05 and 0.5% significant at α-level 0.10; 27.6% < 0.0; one-sample one-sided t-test vs 0: t(999) = 18.9, p = 1.

Given the low sample size N = 29 unique families, relatively few effect sizes are big enough to be significant for each individual analysis; however, there are many more significant ACMEs for ASPM-D than for MCPH1-D: 0.1% vs 0.2% (0.5 times) for α-level 0.05, and 4.3% vs 0.5% (8.6 times) for α-level 0.10.

brms

Figure 143. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 144. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 145. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

All data

With Africa and tone1 coded numerically, the model fit is: χ2(1)=0.00, p=0.96; CFI=1.00, TLI=1.03, NNFI=1.03 and RFI=1.00:

Figure 146. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as numeric binary (tone_bin_num with Yes=1 and Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Likewise, with Africa and tone1 coded as ordered binary factors, the model fit is: χ2(1)=0.01, p=0.94; CFI=1.00, TLI=1.66, NNFI=1.66 and RFI=1.00:

Figure 147. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as ordered binary factors (tone_bin_ord with No < Yes, and Africa_ord with outside Africa < in Africa); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Restricted sampling
***Figure 148.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 148. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

  • models fits:

    • 100% of the p-values are not significant
    • mean(CFI) = 1, median(CFI) = 1, sd(CFI) = 0.01, IQR(CFI) = 0
    • mean(TLI) = 1.04, median(TLI) = 1.06, sd(TLI) = 0.07, IQR(TLI) = 0.08
    • mean(NNFI) = 1.04, median(NNFI) = 1.06, sd(NNFI) = 0.07, IQR(NNFI) = 0.08
    • mean(RFI) = 0.94, median(RFI) = 0.96, sd(RFI) = 0.06, IQR(RFI) = 0.08
  • Africa → ASPM-D: mean = -0.83, median = -0.85, sd = 0.11, IQR = 0.14, 100.0% < 0; 95.6% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -2.4e+02, p = 0;

  • Africa → MCPH1-D: mean = -2.3, median = -2.3, sd = 0.077, IQR = 0.099, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -9.5e+02, p = 0;

  • Africa → tone1: mean = 0.45, median = 0.47, sd = 0.3, IQR = 0.44, 92.2% > 0; 12.4% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 47, p = 5.6e-253;

  • ASPM-D → tone1: mean = -0.057, median = -0.057, sd = 0.071, IQR = 0.11, 76.0% < 0; 10.8% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -25, p = 2.3e-110;

  • MCPH1-D → tone1: mean = 0.057, median = 0.064, as = 0.11, IQR = 0.16, 30.4% < 0; 0.9% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 16, p = 1.

tone2

The resulting dataset has 106 observations, distributed among 73 unique Glottolg codes in 29 families (ranging from a minimum of 1 language per family to a maximum of 37, with a mean 3.7 and median 2 languages per family) and 4 macroareas.

There are 93:78:73 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 17 58 5 4 84
Yes 9 13 0 0 22
Sum 26 71 5 4 106
***Figure 149.*** _Distribution of *tone2*._

Figure 149. Distribution of tone2.

***Figure 150.*** _Map of *tone2*._

Figure 150. Map of tone2.

***Figure 151.*** _Relationship between *tone2*, *ASPM*-D and *MCPH1*-D._

Figure 151. Relationship between tone2, ASPM-D and MCPH1-D.

Regressions

glmer

All data
  • null model: R2 = 0.0%, ICC = 94.9%
  • macroarea: pmacroarea/null = 0.21
  • ASPM:
    • by itself: R2 = 3.7%, β = -1.78 ± 1.25, pASPM/null = 0.072
    • quadratic: R2 = 50.0%, βASPM2 = -8.21 ± 6.07, pASPM2/ASPM = 0.0044
    • with macroarea: R2 = 52.7%, pmacroarea/ASPM = 0.52, pASPM/macroarea = 0.33
  • MCPH1:
    • by itself: R2 = 3.3%, β = -1.30 ± 0.94, pMCPH1/null = 0.13
    • quadratic: R2 = 24.3%, βMCPH12 = -1.39 ± 0.93, pMCPH12/MCPH1 = 0.06
    • with macroarea: R2 = 47.0%, pmacroarea/MCPH1 = 0.43, pMCPH1/macroarea = 0.52
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 5.1%, βASPM = -1.38 ± 1.32, pASPM/MCPH1 = 0.22, βMCPH1 = -0.72 ± 1.03, pMCPH1/ASPM = 0.48, pASPM+MCPH1/null = 0.15,
    • interaction: R2 = 6.9%, pASPM:MCPH1/ASPM+MCPH1 = 0.69
Randomization

I performed 1000 independent replications of each of these parameter combinations, and below are the distributions of the permuted values versus the original ones (i.e., those obtained on the original, non-permuted data).

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 5% 6% 0% 6% 1%
unrestricted none alleles-together 20% 9% 8% 3% 9% 13%
unrestricted none alleles-independent 23% 9% 8% 2% 8% 9%
unrestricted fixef tone 0% 6% 6% 0% 6% 91%
unrestricted fixef alleles-together 60% 9% 9% 5% 8% 92%
unrestricted fixef alleles-independent 62% 9% 7% 3% 9% 94%
macroareas none tone 0% 19% 3% 0% 28% 13%
macroareas none alleles-together 46% 19% 4% 10% 24% 78%
macroareas none alleles-independent 48% 23% 8% 15% 25% 79%
macroareas fixef tone 0% 6% 6% 0% 5% 90%
macroareas fixef alleles-together 54% 6% 6% 13% 7% 73%
macroareas fixef alleles-independent 55% 7% 8% 15% 7% 79%
families none tone 6% 10% 5% 13% 3% 26%
families none alleles-together 18% 8% 8% 18% 0% 18%
families none alleles-independent 18% 8% 12% 19% 3% 23%
families fixef tone 6% 6% 9% 28% 3% 90%
families fixef alleles-together 70% 8% 6% 25% 10% 31%
families fixef alleles-independent 66% 10% 8% 17% 11% 35%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 152.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 87.8% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -38.2, mean = -0.27, *p* = 5.6e-198), 93%, when controlling for the macroarea (*t*(999) = -45.5, mean = -0.48, *p* = 9.2e-246), and 94.3% when controlling for both macroarea and *MCPH1* (*t*(999) = -44.1, mean = -0.60, *p* = 9.5e-237). For *MCPH1*-D (right): 82.5% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -35.5, mean = -0.29, *p* = 2.7e-179), 13.3% when controlling for the macroarea (*t*(999) = 32.3, mean = 0.86, *p* = 1), and 12.6% when controlling for both macroarea and *ASPM* (*t*(999) = 30.9, mean = 1.08, *p* = 1)._

Figure 152. Results for 1000 restricted samplings. For ASPM-D (left): 87.8% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -38.2, mean = -0.27, p = 5.6e-198), 93%, when controlling for the macroarea (t(999) = -45.5, mean = -0.48, p = 9.2e-246), and 94.3% when controlling for both macroarea and MCPH1 (t(999) = -44.1, mean = -0.60, p = 9.5e-237). For MCPH1-D (right): 82.5% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -35.5, mean = -0.29, p = 2.7e-179), 13.3% when controlling for the macroarea (t(999) = 32.3, mean = 0.86, p = 1), and 12.6% when controlling for both macroarea and ASPM (t(999) = 30.9, mean = 1.08, p = 1).

brms

  • ASPM only:
    • β = -1.33, 89%HDI = [-2.91, 0.32]
    • posterior probability p(β<0) = 0.92 (evidence ratio = 11), p(β=0) = 0.57 (evidence ratio = 1.3)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 6.9%; pROPE = 0.061
    • comparison ‘null’ vs ‘ASPM’: [B= L= W=(45%:55%) K=]: anecdotal evidence for null against ASPM (BF=1.26), LOO=0.33 [SE=1.05], WAIC=-0.20 [SE=0.94], KFOLD=-0.02 [SE=2.27]
    • comparison ‘null’ vs ‘ASPM’: [B= L= W=(45%:55%) K=]: anecdotal evidence for null against ASPM (BF=1.26), LOO=0.33 [SE=1.05], WAIC=-0.20 [SE=0.94], KFOLD=-0.02 [SE=2.27]
  • MCPH1 only:
    • β = -0.9, 89%HDI = [-2.89, 0.76]
    • posterior probability p(β<0) = 0.8 (evidence ratio = 3.9), p(β=0) = 0.66 (evidence ratio = 2)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 10.1%; pROPE = 0.09
    • comparison ‘null’ vs ‘MCPH1’: [B= L= W<(37%:63%) K=]: anecdotal evidence for null against MCPH1 (BF=1.69), LOO=0.55 [SE=0.68], WAIC=-0.51 [SE=0.47], KFOLD=-0.29 [SE=2.45]
    • comparison ‘null’ vs ‘MCPH1’: [B= L= W<(37%:63%) K=]: anecdotal evidence for null against MCPH1 (BF=1.69), LOO=0.55 [SE=0.68], WAIC=-0.51 [SE=0.47], KFOLD=-0.29 [SE=2.45]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B> L= W=(30%:70%) K=]: moderate evidence for null against both (BF=3.62), LOO=-0.09 [SE=1.10], WAIC=-0.86 [SE=1.02], KFOLD=0.92 [SE=1.18]
    • interaction:
      • posterior probability p(=0) = 0.7 (evidence ratio = 2.4)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 11.7%; pROPE = 0.104
      • comparison ‘no interaction’ vs ‘with interaction’: [B= L> W=(58%:42%) K>]: anecdotal evidence for no interaction against with interaction (BF=2.54), LOO=1.33 [SE=0.81], WAIC=0.34 [SE=0.41], KFOLD=3.94 [SE=2.20]
    • ASPM (partial):
      • β = -1.22, 89%HDI = [-2.99, 0.53]
      • posterior probability p(β<0) = 0.88 (evidence ratio = 7), p(β=0) = 0.64 (evidence ratio = 1.7)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 8.6%; pROPE = 0.077
    • MCPH1 (partial):
      • β = -0.59, 89%HDI = [-2.52, 1.43]
      • posterior probability p(β<0) = 0.7 (evidence ratio = 2.3), p(β=0) = 0.72 (evidence ratio = 2.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 12.7%; pROPE = 0.114
***Figure 153.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 153.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 153. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 154.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 154.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 154. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 155.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 155.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 155. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 156.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 156.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 156. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Mediation and path analysis

Mediation analysis

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 0.20 (0.01, 0.40), p=0.036, decomposed into:

  • average direct effect (ADE): 0.01 (-0.18, 0.25), p=0.96, and

  • average indirect effect (ACME) mediated by ASPM-D: 0.19 (0.02, 0.34), p=0.024, mediating 95.9% (-1.7%, 470.4%), p=0.052 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.34 ±0.18, p=7.4e-11, and
    • effect of ASPM-D on tone: -0.86 ±0.39, p=0.028.

For MCPH1-D:

  • TE: 0.18 (-0.01, 0.39), p=0.064, decomposed into:

  • ADE: 0.30 (-0.15, 0.63), p=0.17, and

  • ACME: -0.12 (-0.39, 0.28), p=0.46, mediating -72.3% (-674.6%, 386.6%), p=0.5 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.08 ±0.10, p=7.6e-39, and
    • effect of MCPH1-D on tone: 0.47 ±0.63, p=0.46.
Restricted sampling
***Figure 157.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM*-D and *MCPH1*-D; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted)._

Figure 157. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM-D and MCPH1-D; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted).

For ASPM-D:

  • TE: mean = 0.15, median = 0.15; 0.7% significant at α-level 0.05 and 4.8% significant at α-level 0.10; 90.1% > 0.0; one-sample one-sided t-test vs 0: t(999) = 50.2, p = 7.1e-276;

  • ADE: mean = 0.13, median = 0.13; 0.1% significant at α-level 0.05 and 2.4% significant at α-level 0.10; 90.7% > 0.0; one-sample one-sided t-test vs 0: t(999) = 46.1, p = 1.3e-249;

  • ACME: mean = 0.016, median = 0.016; 0.0% significant at α-level 0.05 and 0.0% significant at α-level 0.10; 71.4% > 0.0; one-sample one-sided t-test vs 0: t(999) = 19.0, p = 5e-69;

  • β(Africa → allele): mean = -0.88, median = -0.88; 93.2% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -433.7, p = 0;

  • β(allele → tone | Africa): mean = -0.097, median = -0.11; 0.0% significant at α-level 0.05 and 0.0% significant at α-level 0.10; 69.5% < 0.0; one-sample one-sided t-test vs 0: t(999) = -14.6, p = 3.1e-44.

For MCPH1-D:

  • TE: mean = 0.15, median = 0.15; 0.9% significant at α-level 0.05 and 4.8% significant at α-level 0.10; 90.1% > 0.0; one-sample one-sided t-test vs 0: t(999) = 49.6, p = 3.8e-272;

  • ADE: mean = 0.12, median = 0.12; 0.0% significant at α-level 0.05 and 0.1% significant at α-level 0.10; 81.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 28.7, p = 7e-133;

  • ACME: mean = 0.024, median = 0.023; 0.0% significant at α-level 0.05 and 0.0% significant at α-level 0.10; 55.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 5.7, p = 7.3e-09;

  • β(Africa → allele): mean = -2.3, median = -2.3; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -1219.2, p = 0;

  • β(allele → tone | Africa): mean = 0.033, median = 0.021; 0.0% significant at α-level 0.05 and 0.0% significant at α-level 0.10; 48.5% < 0.0; one-sample one-sided t-test vs 0: t(999) = 1.9, p = 0.97.

Given the low sample size N = 29 unique families, relatively few effect sizes are big enough to be significant for each individual analysis; however, there are many more significant ACMEs for ASPM-D than for MCPH1-D: 0.0% vs 0.0% (NaN times) for α-level 0.05, and 0.0% vs 0.0% (NaN times) for α-level 0.10.

brms

Figure 158. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 159. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 160. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

All data

With Africa and tone1 coded numerically, the model fit is: χ2(1)=0.03, p=0.86; CFI=1.00, TLI=1.03, NNFI=1.03 and RFI=1.00:

Figure 161. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as numeric binary (tone_complex_num with Yes=1 and Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Likewise, with Africa and tone1 coded as ordered binary factors, the model fit is: χ2(1)=0.07, p=0.79; CFI=1.00, TLI=1.61, NNFI=1.61 and RFI=0.97:

Figure 162. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as ordered binary factors (tone_complex_ord with No < Yes, and Africa_ord with outside Africa < in Africa); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Restricted sampling
***Figure 163.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 163. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

  • models fits:

    • 100% of the p-values are not significant
    • mean(CFI) = 1, median(CFI) = 1, sd(CFI) = 0.01, IQR(CFI) = 0
    • mean(TLI) = 1.04, median(TLI) = 1.05, sd(TLI) = 0.06, IQR(TLI) = 0.08
    • mean(NNFI) = 1.04, median(NNFI) = 1.05, sd(NNFI) = 0.06, IQR(NNFI) = 0.08
    • mean(RFI) = 0.94, median(RFI) = 0.95, sd(RFI) = 0.06, IQR(RFI) = 0.07
  • Africa → ASPM-D: mean = -0.88, median = -0.89, sd = 0.062, IQR = 0.084, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -4.5e+02, p = 0;

  • Africa → MCPH1-D: mean = -2.3, median = -2.3, sd = 0.056, IQR = 0.074, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -1.3e+03, p = 0;

  • Africa → tone1: mean = 0.12, median = 0.11, sd = 0.21, IQR = 0.3, 69.9% > 0; 0.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 18, p = 5.9e-64;

  • ASPM-D → tone1: mean = -0.013, median = -0.013, sd = 0.028, IQR = 0.039, 67.2% < 0; 0.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -14, p = 3.9e-41;

  • MCPH1-D → tone1: mean = -0.004, median = -0.0039, as = 0.09, IQR = 0.13, 51.1% < 0; 0.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -1.4, p = 0.08.

Tone counts

The resulting dataset has 110 observations, distributed among 76 unique Glottolg codes in 29 families (ranging from a minimum of 1 language per family to a maximum of 37, with a mean 3.8 and median 2 languages per family) and 4 macroareas.

There are 93:78:76 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
0 6 52 2 3 63
1 6 6 3 0 15
2 12 2 0 1 15
3 2 3 0 0 5
4 0 6 0 0 6
5 1 3 0 0 4
6 0 2 0 0 2
Sum 27 74 5 4 110
***Figure 164.*** _Distribution of tone *counts*._

Figure 164. Distribution of tone counts.

***Figure 165.*** _Distribution of tone *counts* across the world._

Figure 165. Distribution of tone counts across the world.

***Figure 166.*** _Relationship between tone *counts* (colors) and the two alleles (frequency) by macroarea._

Figure 166. Relationship between tone counts (colors) and the two alleles (frequency) by macroarea.

Regressions

glmer

All data
  • null model: R2 = 0.0%, ICC = 100.0%
  • the Poisson model is not overdispersed: χ2(108) = 68.4, p = 1
  • macroarea: pmacroarea/null = 0.22
  • ASPM:
    • by itself: R2 = 5.7%, β = -0.28 ± 0.23, pASPM/null = 0.22
    • quadratic: R2 = 9.6%, βASPM2 = -0.24 ± 0.23, pASPM2/ASPM = 0.41
    • with macroarea: R2 = 17.6%, pmacroarea/ASPM = 0.37, pASPM/macroarea = 0.62
  • MCPH1:
    • by itself: R2 = 10.2%, β = -0.40 ± 0.21, pMCPH1/null = 0.064
    • quadratic: R2 = 12.8%, βMCPH12 = -0.39 ± 0.21, pMCPH12/MCPH1 = 0.31
    • with macroarea: R2 = 15.8%, pmacroarea/MCPH1 = 0.78, pMCPH1/macroarea = 0.76
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 14.0%, βASPM = -0.18 ± 0.24, pASPM/MCPH1 = 0.44, βMCPH1 = -0.34 ± 0.22, pMCPH1/ASPM = 0.11, pASPM+MCPH1/null = 0.13,
    • interaction: R2 = 14.0%, pASPM:MCPH1/ASPM+MCPH1 = 0.9
Randomization

We performed 1000 independent replications:

Regressions with randomizations for tone counts.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 18% 16% 15% 13% 4%
unrestricted none alleles-together 11% 4% 3% 6% 4% 0%
unrestricted none alleles-independent 10% 3% 4% 5% 3% 0%
unrestricted fixef tone 0% 24% 18% 26% 18% 34%
unrestricted fixef alleles-together 86% 3% 3% 15% 4% 19%
unrestricted fixef alleles-independent 84% 3% 4% 12% 3% 15%
macroareas none tone 0% 40% 20% 18% 33% 22%
macroareas none alleles-together 32% 15% 4% 16% 17% 25%
macroareas none alleles-independent 30% 12% 4% 18% 16% 23%
macroareas fixef tone 0% 34% 24% 33% 22% 38%
macroareas fixef alleles-together 85% 4% 5% 21% 4% 35%
macroareas fixef alleles-independent 86% 3% 4% 19% 4% 33%
families none tone 11% 6% 8% 49% 2% 6%
families none alleles-together 24% 10% 14% 66% 0% 3%
families none alleles-independent 26% 9% 15% 65% 0% 5%
families fixef tone 17% 7% 12% 67% 1% 49%
families fixef alleles-together 86% 2% 6% 58% 1% 3%
families fixef alleles-independent 83% 2% 6% 53% 1% 6%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 167.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 97.7% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -57.2, mean = -0.35, *p* = 8.7e-318), 88.4%, when controlling for the macroarea (*t*(999) = -35.2, mean = -0.31, *p* = 2.6e-177), and 88.5% when controlling for both macroarea and *MCPH1* (*t*(999) = -36.1, mean = -0.33, *p* = 2.6e-183). For *MCPH1*-D (right): 99.9% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -77.4, mean = -0.31, *p* = 0), 50.8% when controlling for the macroarea (*t*(999) = 1.5, mean = 0.02, *p* = 0.93), and 44.1% when controlling for both macroarea and *ASPM* (*t*(999) = 7.5, mean = 0.10, *p* = 1)._

Figure 167. Results for 1000 restricted samplings. For ASPM-D (left): 97.7% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -57.2, mean = -0.35, p = 8.7e-318), 88.4%, when controlling for the macroarea (t(999) = -35.2, mean = -0.31, p = 2.6e-177), and 88.5% when controlling for both macroarea and MCPH1 (t(999) = -36.1, mean = -0.33, p = 2.6e-183). For MCPH1-D (right): 99.9% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -77.4, mean = -0.31, p = 0), 50.8% when controlling for the macroarea (t(999) = 1.5, mean = 0.02, p = 0.93), and 44.1% when controlling for both macroarea and ASPM (t(999) = 7.5, mean = 0.10, p = 1).

brms

  • ASPM only:
    • β = -0.2, 89%HDI = [-0.65, 0.24]
    • posterior probability p(β<0) = 0.77 (evidence ratio = 3.3), p(β=0) = 0.9 (evidence ratio = 9.1)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 24.7%; pROPE = 0.22
    • comparison ‘null’ vs ‘ASPM’: [B> L> W>(83%:17%) K>]: moderate evidence for null against ASPM (BF=6.54), LOO=1.59 [SE=0.82], WAIC=1.60 [SE=0.85], KFOLD=2.27 [SE=1.55]
  • MCPH1 only:
    • β = -0.3, 89%HDI = [-0.79, 0.18]
    • posterior probability p(β<0) = 0.84 (evidence ratio = 5.5), p(β=0) = 0.86 (evidence ratio = 6.2)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 15.8%; pROPE = 0.141
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(58%:42%) K>]: moderate evidence for null against MCPH1 (BF=5.03), LOO=0.07 [SE=0.70], WAIC=0.32 [SE=0.59], KFOLD=1.38 [SE=0.83]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L> W>(81%:19%) K>>]: very strong evidence for null against both (BF=67.8), LOO=1.39 [SE=0.84], WAIC=1.42 [SE=1.02], KFOLD=4.66 [SE=1.61]
    • interaction:
      • posterior probability p(=0) = 0.9 (evidence ratio = 8.7)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 24%; pROPE = 0.214
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L= W=(58%:42%) K<]: moderate evidence for no interaction against with interaction (BF=8.92), LOO=0.36 [SE=0.71], WAIC=0.31 [SE=0.37], KFOLD=-6.87 [SE=3.51]
    • ASPM (partial):
      • β = -0.17, 89%HDI = [-0.61, 0.24]
      • posterior probability p(β<0) = 0.74 (evidence ratio = 2.9), p(β=0) = 0.91 (evidence ratio = 9.7)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 27%; pROPE = 0.24
    • MCPH1 (partial):
      • β = -0.27, 89%HDI = [-0.77, 0.20]
      • posterior probability p(β<0) = 0.82 (evidence ratio = 4.7), p(β=0) = 0.86 (evidence ratio = 6.3)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 17.3%; pROPE = 0.154
***Figure 168.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 168.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 168. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 169.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 169.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 169. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 170.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 170.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 170. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

Mediation analysis

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 0.81 (0.19, 1.64), p=0.006, decomposed into:

  • average direct effect (ADE): -0.20 (-0.91, 0.42), p=0.53, and

  • average indirect effect (ACME) mediated by ASPM-D: 1.01 (0.49, 1.89), p=0, mediating 124.1% (61.9%, 380.1%), p=0.006 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.34 ±0.18, p=3.1e-11, and
    • effect of ASPM-D on tone: -0.58 ±0.14, p=3.9e-05.

For MCPH1-D:

  • TE: 0.62 (0.13, 1.17), p=0.018, decomposed into:

  • ADE: 0.62 (-0.69, 2.13), p=0.35, and

  • ACME: 0.00 (-1.26, 1.27), p=1, mediating 0.3% (-277.8%, 294.1%), p=1 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.07 ±0.10, p=1e-39, and
    • effect of MCPH1-D on tone: -0.01 ±0.22, p=0.96.
Restricted sampling
***Figure 171.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM* and *MCPH1*; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (dotted), 0.05 (solid) and 0.10 (dashed)._

Figure 171. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM and MCPH1; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (dotted), 0.05 (solid) and 0.10 (dashed).

For ASPM-D:

  • TE: mean = 1.2, median = 1.1; 55.1% significant at α-level 0.05 and 65.0% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 72.9, p = 0;

  • ADE: mean = 0.91, median = 0.9; 32.4% significant at α-level 0.05 and 46.1% significant at α-level 0.10; 98.3% > 0.0; one-sample one-sided t-test vs 0: t(999) = 60.8, p = 0;

  • ACME: mean = 0.26, median = 0.22; 3.0% significant at α-level 0.05 and 11.2% significant at α-level 0.10; 78.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 25.7, p = 8.1e-113;

  • β(Africa → allele): mean = -0.89, median = -0.89; 92.1% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -447.7, p = 0;

  • β(allele → tone | Africa): mean = -0.18, median = -0.17; 6.5% significant at α-level 0.05 and 14.2% significant at α-level 0.10; 78.7% < 0.0; one-sample one-sided t-test vs 0: t(999) = -27.1, p = 3.3e-122.

For MCPH1-D:

  • TE: mean = 1.1, median = 1.1; 55.6% significant at α-level 0.05 and 64.9% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 74.9, p = 0;

  • ADE: mean = 0.79, median = 0.74; 1.1% significant at α-level 0.05 and 3.7% significant at α-level 0.10; 70.7% > 0.0; one-sample one-sided t-test vs 0: t(999) = 15.0, p = 1.6e-46;

  • ACME: mean = 0.31, median = 0.36; 0.2% significant at α-level 0.05 and 2.9% significant at α-level 0.10; 60.7% > 0.0; one-sample one-sided t-test vs 0: t(999) = 5.7, p = 8.9e-09;

  • β(Africa → allele): mean = -2.3, median = -2.3; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -1254.2, p = 0;

  • β(allele → tone | Africa): mean = -0.12, median = -0.13; 0.4% significant at α-level 0.05 and 2.7% significant at α-level 0.10; 67.5% < 0.0; one-sample one-sided t-test vs 0: t(999) = -13.5, p = 1.3e-38.

Given the low sample size N = 35 unique families, relatively few effect sizes are big enough to be significant; however, there are many more significant indirect effects (ACME) for ASPM-D than for MCPH1-D: 6.5% vs 0.4% (16.2 times) for α-level 0.05, and 14.2% vs 2.7% (5.3 times) for α-level 0.10.

brms

Figure 172. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 173. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 174. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

Please note that path analysis uses a linear model (so not a Poisson one) for the tone counts; also I only use the numeric coding for Africa.

All data

Coding Africa numerically, the model fits the data very well (χ2(1)=0.02, p=0.88; CFI=1.00, TLI=1.03, NNFI=1.03 and RFI=1.00):

Figure 175. Path analysis model with standardised coefficients and significance stars. Here, macroarea (Africa vs non-Africa) is coded as numeric binary (Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D..

Restricted sampling
***Figure 176.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 176. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

It can be seen that:

  • the models fits:

    • 100% of the p-values are not significant
    • mean(CFI) = 1, median(CFI) = 1, sd(CFI) = 0, IQR(CFI) = 0
    • mean(TLI) = 1.04, median(TLI) = 1.05, sd(TLI) = 0.06, IQR(TLI) = 0.07
    • mean(NNFI) = 1.04, median(NNFI) = 1.05, sd(NNFI) = 0.06, IQR(NNFI) = 0.07
    • mean(RFI) = 0.94, median(RFI) = 0.95, sd(RFI) = 0.05, IQR(RFI) = 0.07
  • Africa → ASPM-D: mean = -0.89, median = -0.89, sd = 0.064, IQR = 0.084, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -4.4e+02, p = 0

  • Africa → MCPH1-D: mean = -2.3, median = -2.3, sd = 0.057, IQR = 0.078, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -1.3e+03, p = 0

  • Africa → tone counts: mean = 0.45, median = 0.49, sd = 0.89, IQR = 1.2, 70.2% > 0; 3.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 16, p = 1.1e-51

  • ASPM-D → tone counts: mean = -0.16, median = -0.16, sd = 0.19, IQR = 0.26, 79.9% < 0; 7.3% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -27, p = 2.7e-122

  • MCPH1-D → tone counts: mean = -0.18, median = -0.18, as = 0.37, IQR = 0.51, 69.2% < 0; 0.1% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -16, p = 4.7e-49

Appendix IV: Excluding ambiguous samples

The correspondence between genetic samples and languages is given below (excluding the 139 samples that unambiguously correspond to a single language):

Genetic samples corresponding to more than 1 language.
pop_ID n_languages n_families languages families
SA004382R 144 1 ’Are’are, Adzera, Äiwoo, Ajië, Amara, Aneityum, Araki, Aribwatsa, Arop-Lokep, Arosi, Aulua, Babatana, Bannoni, Big Nambas, Carolinian, Cemuhî, Cheke Holo, Chuukese, Dehu, Dumbea, East Ambae, East Futuna, East Uvean, Fijian, Futuna-Aniwa, Fwâi, Gapapaiwa, Gela, Gilbertese, Gumawana, Halia, Hano, Hawaiian, Hoava, Iaai, Iduna, Kairiru, Kapingamarangi, Kara (Papua New Guinea), Kaulong, Kela (Papua New Guinea), Kele (Papua New Guinea), Kilivila, Kokota, Kosraean, Kuanua, Kwaio, Kwamera, Labu, Lala, Lamenu, Lau, Lenakel, Lewo, Longgu, Loniu, Lonwolwol, Lou, Luangiua, Lusi, Maisin, Maleu-Kilenge, Manam, Maori, Marshallese, Matukar, Mbula, Mekeo, Mele-Fila, Minaveha, Mokilese, Mono-Alu, Motu, Muduapa, Musom, Mussau-Emira, Muyuw, Mwotlap, Nakanai, Nalik, Natügu, Nauru, Nehan, Nêlêmwa-Nixumwak, Nengone, Neve’ei, Niuafo’ou, Niuean, North Efate, North Marquesan, Nukuoro, Paama, Patep, Patpatar, Pingelapese, Pohnpeian, Port Sandwich, Puluwatese, Rapanui, Rennell-Bellona, Rotuman, Roviana, Sa’a, Saliba, Samoan, Saposa, Siar-Lak, Sie, Sinaugoro, Sio, Sobei, Sonsorol, South Efate, South Marquesan, Southwest Tanna, Sudest, Sursurunga, Tahitian, Takia, Tamambo, Tawala, Teanu, Teop, Tigak, Tirax, Tiri-Mea, To’abaita, Tobati, Tokelau, Tonga (Tonga Islands), Tuamotuan, Tumleo, Tungag, Tuvalu, Ulithian, Ura (Vanuatu), Uripiv-Wala-Rano-Atchin, Vaeakau-Taumako, Waima, Wanohe, Western Fijian, Woleaian, Xârâcùù, Yabem Austronesian
SA001501H 23 4 Abau, Alamblak, Ambulas, Ap Ma, Awtuw, Bahinemo, Boikin, Chambri, Hanga Hundi, Iatmul, Iwam, Kaian, Kire, Kwoma, Manambu, Mehek, Murik (Papua New Guinea), Namia, Rao, Watam, Wogamusin, Yessan-Mayo, Yimas Ap Ma, Lower Sepik-Ramu, Ndu, Sepik
SA001818S 9 1 Herero, Kuanyama, Kwambi, Mbalanhu, Ndonga, Ngandyera, Southern Sotho, Tswana, Zulu Atlantic-Congo
SA004368V 7 1 Amharic, Awngi, Bilin, Geez, Qimant, Tigrinya, Xamtanga Afro-Asiatic
SA004046O 6 1 Bukusu, Idakho-Isukha-Tiriki, Kisa, Masaaba, Saamia, Tsotso Atlantic-Congo
SA001469U 5 3 East Taa, Hai//om-Akhoe, Nama (Namibia), North-Central Ju, South-Eastern Ju Khoe-Kwadi, Kxa, Tuu
SA001467S 4 1 Eastern Maninkakan, Kita Maninkakan, Mandinka, Western Maninkakan Mande
SA001819T 4 1 Gusii, Kamba (Kenya), Kikuyu, Meru Atlantic-Congo
SA003646T 4 1 Eastern Maninkakan, Kita Maninkakan, Mandinka, Western Maninkakan Mande
SA001476S 3 1 Eastern Balochi, Southern Balochi, Western Balochi Indo-European
SA001478U 3 1 Eastern Balochi, Southern Balochi, Western Balochi Indo-European
SA004365S 3 1 Kahe, Machame, Mochi Atlantic-Congo
SA004371P 3 1 Modern Hebrew, South Levantine Arabic, Standard Arabic Afro-Asiatic
ESTONIAN_VAR 2 1 Estonian, South Estonian Uralic
MB2005_BakolaPygmy 2 1 Gyele, Kwasio Atlantic-Congo
Qatari 2 1 Gulf Arabic, Standard Arabic Afro-Asiatic
SA001466R 2 1 Efe, Lese Central Sudanic
SA001474Q 2 1 South Levantine Arabic, Standard Arabic Afro-Asiatic
SA001483Q 2 1 Mandarin Chinese, Yue Chinese Sino-Tibetan
SA001486T 2 1 Central Mashan Hmong, Hmong Njua Hmong-Mien
SA001493R 2 1 Lü, Tai Nüa Tai-Kadai
SA001508O 2 1 English, Scots Indo-European
SA002254N 2 1 South Levantine Arabic, Standard Arabic Afro-Asiatic
SA002257Q 2 1 South Levantine Arabic, Standard Arabic Afro-Asiatic
SA002262M 2 1 Central Pashto, Northern Pashto Indo-European
SA003028N 2 1 Estonian, South Estonian Uralic
SA004111H 2 1 English, Spanish Indo-European
SA004238R 2 1 Lü, Tai Nüa Tai-Kadai
SA004361O 2 1 Efe, Lese Central Sudanic
SA004370O 2 1 Judeo-Yemeni Arabic, Modern Hebrew Afro-Asiatic
SA004378W 2 1 English, Irish Indo-European
SA004587Y 2 1 Mongolia Buriat, Russia Buriat Mongolic-Khitan
SA004592U 2 1 Mandarin Chinese, Yue Chinese Sino-Tibetan
SA004599B 2 1 Erzya, Moksha Uralic
SA004603N 2 1 Church Slavic, Russian Indo-European
SA004623P 2 1 Georgian, Mingrelian Kartvelian

Even if it is very conservative (e.g., Church Slavic and Russian corresponding to SA004603N are very similar for tone, as are Modern Hebrew, South Levantine Arabic and Standard Arabic corresponding to SA004371P), I removed from this analysis all genetic samples that map to more than 1 language.

This results in 139 unique genetic samples corresponding to 103 (meta)populations, each mapping to a single language, distributed across 91 unique languages (i.e., it is still the case that more than one sample maps to the same language) in 4 macroareas:

Africa Eurasia America Papunesia
16 109 10 4

tone1

There are 126 observations, distributed among 88 unique Glottolg codes in 30 families (ranging from a minimum of 1 language per family to a maximum of 37, with a mean 4.2 and median 2 languages per family) and 4 macroareas.

There are 126:100:88 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 2 79 4 4 89
Yes 14 17 6 0 37
Sum 16 96 10 4 126
***Figure 177.*** _Distribution of *tone1*._

Figure 177. Distribution of tone1.

***Figure 178.*** _Map of *tone1*._

Figure 178. Map of tone1.

***Figure 179.*** _Relationship between *tone1*, *ASPM*-D and *MCPH1*-D._

Figure 179. Relationship between tone1, ASPM-D and MCPH1-D.

Regressions

glmer

All data
  • null model: R2 = 0.0%, ICC = 79.9%
  • macroarea: pmacroarea/null = 0.0027
  • ASPM:
    • by itself: R2 = 6.9%, β = -0.92 ± 0.54, pASPM/null = 0.094
    • quadratic: R2 = 6.3%, βASPM2 = -0.91 ± 0.52, pASPM2/ASPM = 0.77
    • with macroarea: R2 = 54.9%, pmacroarea/ASPM = 0.008, pASPM/macroarea = 0.48
  • MCPH1:
    • by itself: R2 = 7.1%, β = -1.01 ± 0.47, pMCPH1/null = 0.032
    • quadratic: R2 = 7.2%, βMCPH12 = -1.02 ± 0.47, pMCPH12/MCPH1 = 0.9
    • with macroarea: R2 = 53.3%, pmacroarea/MCPH1 = 0.018, pMCPH1/macroarea = 0.45
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 10.6%, βASPM = -0.58 ± 0.60, pASPM/MCPH1 = 0.36, βMCPH1 = -0.77 ± 0.48, pMCPH1/ASPM = 0.1, pASPM+MCPH1/null = 0.065,
    • interaction: R2 = 10.0%, pASPM:MCPH1/ASPM+MCPH1 = 0.56
Alleles on macroarea

To better understand this overlap between family, macroarea and the two “derived” alleles, I regressed (separately) the ASPM-D and MCPH1-D on the macroarea, using mixed-effects beta regression (after replacing all \(0.0\) values by \(10^{-7}\) and all \(1.0\) by \(1.0-10^{-7}\), respectively) with language family as random effect:

  • the alleles are very strongly clustered within families:
    • ASPM: ICC = 100.0%
    • MCPH1: ICC = 100.0%
  • macroarea predicts their distribution very strongly:
    • ASPM: p = 8.6e-05, R2 = 48.8%
    • MCPH1: p = 6.2e-10, R2 = 77.6%
  • separating Africa vs the rest of the world seems to drive most of this effect (both alleles have lower frequencies in Africa):
    • ASPM: p = 0.023, R2 = 15.8%
    • MCPH1: p = 3.1e-07, R2 = 47.5%
Randomization

I performed 1000 independent replications of each of these parameter combinations, and below are the distributions of the permuted values versus the original ones (i.e., those obtained on the original, non-permuted data).

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 4% 4% 0% 5% 0%
unrestricted none alleles-together 6% 5% 5% 7% 6% 4%
unrestricted none alleles-independent 7% 6% 5% 7% 5% 2%
unrestricted fixef tone 0% 6% 5% 13% 7% 15%
unrestricted fixef alleles-together 70% 6% 5% 25% 6% 19%
unrestricted fixef alleles-independent 67% 6% 6% 24% 5% 16%
macroareas none tone 0% 72% 28% 24% 67% 7%
macroareas none alleles-together 30% 24% 8% 28% 20% 40%
macroareas none alleles-independent 35% 29% 14% 37% 25% 46%
macroareas fixef tone 0% 5% 5% 14% 6% 21%
macroareas fixef alleles-together 64% 4% 4% 24% 5% 28%
macroareas fixef alleles-independent 64% 5% 4% 27% 4% 26%
families none tone 44% 21% 5% 24% 16% 38%
families none alleles-together 18% 15% 6% 32% 6% 17%
families none alleles-independent 30% 27% 20% 49% 19% 27%
families fixef tone 27% 6% 4% 37% 4% 38%
families fixef alleles-together 70% 8% 6% 50% 3% 24%
families fixef alleles-independent 74% 8% 10% 52% 5% 35%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 180.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 100% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -137.3, mean = -1.04, *p* = 0), 99.5%, when controlling for the macroarea (*t*(999) = -76.0, mean = -0.95, *p* = 0), and 99.5% when controlling for both macroarea and *MCPH1* (*t*(999) = -67.1, mean = -1.13, *p* = 0). For *MCPH1*-D (right): 100% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -100.4, mean = -0.78, *p* = 0), 92.4% when controlling for the macroarea (*t*(999) = -45.7, mean = -1.42, *p* = 1.4e-247), and 92.5% when controlling for both macroarea and *ASPM* (*t*(999) = -47.9, mean = -1.75, *p* = 3.3e-261)._

Figure 180. Results for 1000 restricted samplings. For ASPM-D (left): 100% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -137.3, mean = -1.04, p = 0), 99.5%, when controlling for the macroarea (t(999) = -76.0, mean = -0.95, p = 0), and 99.5% when controlling for both macroarea and MCPH1 (t(999) = -67.1, mean = -1.13, p = 0). For MCPH1-D (right): 100% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -100.4, mean = -0.78, p = 0), 92.4% when controlling for the macroarea (t(999) = -45.7, mean = -1.42, p = 1.4e-247), and 92.5% when controlling for both macroarea and ASPM (t(999) = -47.9, mean = -1.75, p = 3.3e-261).

brms

  • ASPM only:
    • β = -1.17, 89%HDI = [-3.06, 0.82]
    • posterior probability p(β<0) = 0.84 (evidence ratio = 5.2), p(β=0) = 0.66 (evidence ratio = 1.9)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 9%; pROPE = 0.08
    • comparison ‘null’ vs ‘ASPM’: [B= L< W<(15%:85%) K=]: anecdotal evidence for null against ASPM (BF=1.85), LOO=-2.20 [SE=1.49], WAIC=-1.73 [SE=0.89], KFOLD=0.55 [SE=2.12]
    • comparison ‘null’ vs ‘ASPM’: [B= L< W<(15%:85%) K=]: anecdotal evidence for null against ASPM (BF=1.85), LOO=-2.20 [SE=1.49], WAIC=-1.73 [SE=0.89], KFOLD=0.55 [SE=2.12]
  • MCPH1 only:
    • β = -1.5, 89%HDI = [-3.58, 0.81]
    • posterior probability p(β<0) = 0.87 (evidence ratio = 7), p(β=0) = 0.59 (evidence ratio = 1.4)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 6.7%; pROPE = 0.06
    • comparison ‘null’ vs ‘MCPH1’: [B= L<< W<<(7%:93%) K<]: anecdotal evidence for null against MCPH1 (BF=1.44), LOO=-3.54 [SE=1.49], WAIC=-2.57 [SE=0.77], KFOLD=-2.53 [SE=1.67]
    • comparison ‘null’ vs ‘MCPH1’: [B= L<< W<<(7%:93%) K<]: anecdotal evidence for null against MCPH1 (BF=1.44), LOO=-3.54 [SE=1.49], WAIC=-2.57 [SE=0.77], KFOLD=-2.53 [SE=1.67]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B> L<< W<<(1%:99%) K=]: moderate evidence for null against both (BF=3.18), LOO=-4.04 [SE=1.54], WAIC=-4.41 [SE=1.11], KFOLD=-1.87 [SE=2.04]
    • interaction:
      • posterior probability p(=0) = 0.64 (evidence ratio = 1.7)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 8.6%; pROPE = 0.076
      • comparison ‘no interaction’ vs ‘with interaction’: [B= L< W<<(21%:79%) K>]: anecdotal evidence for no interaction against with interaction (BF=1.25), LOO=-1.44 [SE=0.86], WAIC=-1.30 [SE=0.47], KFOLD=1.08 [SE=1.05]
    • ASPM (partial):
      • β = -1.02, 89%HDI = [-3.30, 1.32]
      • posterior probability p(β<0) = 0.77 (evidence ratio = 3.3), p(β=0) = 0.7 (evidence ratio = 2.3)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 11.1%; pROPE = 0.098
    • MCPH1 (partial):
      • β = -1.53, 89%HDI = [-3.91, 0.86]
      • posterior probability p(β<0) = 0.86 (evidence ratio = 6.4), p(β=0) = 0.6 (evidence ratio = 1.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 7.2%; pROPE = 0.064
***Figure 181.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 181.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 181. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 182.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 182.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 182. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 183.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 183.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 183. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 184.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 184.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 184. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Mediation and path analysis

Mediation analysis

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 0.63 (0.37, 0.78), p=0, decomposed into:

  • average direct effect (ADE): 0.44 (0.15, 0.67), p=0, and

  • average indirect effect (ACME) mediated by ASPM-D: 0.19 (0.07, 0.34), p=0, mediating 30.0% (9.7%, 62.3%), p=0 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.17 ±0.25, p=6.3e-06, and
    • effect of ASPM-D on tone: -1.02 ±0.30, p=0.00057.

For MCPH1-D:

  • TE: 0.64 (0.40, 0.79), p=0, decomposed into:

  • ADE: 0.71 (0.38, 0.86), p=0, and

  • ACME: -0.07 (-0.22, 0.22), p=0.37, mediating -12.3% (-51.6%, 35.7%), p=0.37 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.45 ±0.15, p=8.9e-32, and
    • effect of MCPH1-D on tone: 0.40 ±0.44, p=0.37.
Restricted sampling
***Figure 185.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM*-D and *MCPH1*-D; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted)._

Figure 185. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM-D and MCPH1-D; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted).

For ASPM-D:

  • TE: mean = 0.2, median = 0.15; 0.0% significant at α-level 0.05 and 10.4% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 59.0, p = 0;

  • ADE: mean = 0.15, median = 0.11; 0.0% significant at α-level 0.05 and 2.6% significant at α-level 0.10; 98.8% > 0.0; one-sample one-sided t-test vs 0: t(999) = 42.9, p = 5.1e-229;

  • ACME: mean = 0.057, median = 0.056; 0.0% significant at α-level 0.05 and 2.4% significant at α-level 0.10; 99.9% > 0.0; one-sample one-sided t-test vs 0: t(999) = 86.9, p = 0;

  • β(Africa → allele): mean = -0.63, median = -0.67; 5.0% significant at α-level 0.05 and 38.4% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -123.7, p = 0;

  • β(allele → tone | Africa): mean = -0.81, median = -0.8; 8.1% significant at α-level 0.05 and 31.0% significant at α-level 0.10; 99.9% < 0.0; one-sample one-sided t-test vs 0: t(999) = -100.0, p = 0.

For MCPH1-D:

  • TE: mean = 0.2, median = 0.15; 0.0% significant at α-level 0.05 and 10.4% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 57.6, p = 3.9e-320;

  • ADE: mean = 0.22, median = 0.2; 0.1% significant at α-level 0.05 and 2.1% significant at α-level 0.10; 98.9% > 0.0; one-sample one-sided t-test vs 0: t(999) = 58.3, p = 0;

  • ACME: mean = -0.017, median = -0.04; 0.0% significant at α-level 0.05 and 0.5% significant at α-level 0.10; 34.7% > 0.0; one-sample one-sided t-test vs 0: t(999) = -4.9, p = 1;

  • β(Africa → allele): mean = -2.5, median = -2.5; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -487.0, p = 0;

  • β(allele → tone | Africa): mean = 0.37, median = 0.39; 0.0% significant at α-level 0.05 and 0.4% significant at α-level 0.10; 26.3% < 0.0; one-sample one-sided t-test vs 0: t(999) = 21.3, p = 1.

Given the low sample size N = 30 unique families, relatively few effect sizes are big enough to be significant for each individual analysis; however, there are many more significant ACMEs for ASPM-D than for MCPH1-D: 8.1% vs 0.0% (Inf times) for α-level 0.05, and 31.0% vs 0.4% (77.5 times) for α-level 0.10.

brms

Figure 186. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 187. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 188. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

All data

With Africa and tone1 coded numerically, the model fit is: χ2(1)=0.03, p=0.86; CFI=1.00, TLI=1.03, NNFI=1.03 and RFI=1.00:

Figure 189. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as numeric binary (tone_bin_num with Yes=1 and Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Likewise, with Africa and tone1 coded as ordered binary factors, the model fit is: χ2(1)=0.08, p=0.78; CFI=1.00, TLI=1.21, NNFI=1.21 and RFI=0.99:

Figure 190. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as ordered binary factors (tone_bin_ord with No < Yes, and Africa_ord with outside Africa < in Africa); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Restricted sampling
***Figure 191.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 191. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

  • models fits:

    • 80.7% of the p-values are not significant
    • mean(CFI) = 0.98, median(CFI) = 0.99, sd(CFI) = 0.03, IQR(CFI) = 0.04
    • mean(TLI) = 0.9, median(TLI) = 0.96, sd(TLI) = 0.2, IQR(TLI) = 0.27
    • mean(NNFI) = 0.9, median(NNFI) = 0.96, sd(NNFI) = 0.2, IQR(NNFI) = 0.27
    • mean(RFI) = 0.81, median(RFI) = 0.86, sd(RFI) = 0.17, IQR(RFI) = 0.24
  • Africa → ASPM-D: mean = -0.62, median = -0.66, sd = 0.16, IQR = 0.21, 100.0% < 0; 79.4% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -1.2e+02, p = 0;

  • Africa → MCPH1-D: mean = -2.5, median = -2.5, sd = 0.16, IQR = 0.23, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -5.1e+02, p = 0;

  • Africa → tone1: mean = 0.49, median = 0.53, sd = 0.36, IQR = 0.52, 88.1% > 0; 20.3% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 43, p = 4.3e-232;

  • ASPM-D → tone1: mean = -0.16, median = -0.16, sd = 0.051, IQR = 0.069, 99.9% < 0; 52.2% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -1e+02, p = 0;

  • MCPH1-D → tone1: mean = 0.0056, median = 0.02, as = 0.12, IQR = 0.17, 43.1% < 0; 1.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 1.4, p = 0.92.

tone2

The resulting dataset has 121 observations, distributed among 83 unique Glottolg codes in 30 families (ranging from a minimum of 1 language per family to a maximum of 36, with a mean 4 and median 1.5 languages per family) and 4 macroareas.

There are 121:95:83 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 8 82 9 4 103
Yes 6 11 1 0 18
Sum 14 93 10 4 121
***Figure 192.*** _Distribution of *tone2*._

Figure 192. Distribution of tone2.

***Figure 193.*** _Map of *tone2*._

Figure 193. Map of tone2.

***Figure 194.*** _Relationship between *tone2*, *ASPM*-D and *MCPH1*-D._

Figure 194. Relationship between tone2, ASPM-D and MCPH1-D.

Regressions

glmer

All data
  • null model: R2 = 0.0%, ICC = 97.3%
  • macroarea: pmacroarea/null = 0.58
  • ASPM:
    • by itself: R2 = 0.7%, β = -0.89 ± 1.03, pASPM/null = 0.37
    • quadratic: R2 = 51.9%, βASPM2 = -10.31 ± 6.43, pASPM2/ASPM = 0.0089
    • with macroarea: R2 = 11.3%, pmacroarea/ASPM = 0.74, pASPM/macroarea = 0.78
  • MCPH1:
    • by itself: R2 = 1.2%, β = -1.18 ± 0.90, pMCPH1/null = 0.15
    • quadratic: R2 = 2.2%, βMCPH12 = -1.38 ± 0.90, pMCPH12/MCPH1 = 0.31
    • with macroarea: R2 = 8.7%, pmacroarea/MCPH1 = 0.94, pMCPH1/macroarea = 0.47
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 1.5%, βASPM = -0.42 ± 1.20, pASPM/MCPH1 = 0.73, βMCPH1 = -1.05 ± 0.96, pMCPH1/ASPM = 0.24, pASPM+MCPH1/null = 0.33,
    • interaction: R2 = 2.2%, pASPM:MCPH1/ASPM+MCPH1 = 0.68
Randomization

I performed 1000 independent replications of each of these parameter combinations, and below are the distributions of the permuted values versus the original ones (i.e., those obtained on the original, non-permuted data).

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 6% 5% 7% 6% 0%
unrestricted none alleles-together 42% 11% 10% 25% 10% 6%
unrestricted none alleles-independent 42% 9% 9% 28% 7% 4%
unrestricted fixef tone 0% 6% 5% 13% 6% 1%
unrestricted fixef alleles-together 81% 10% 10% 30% 10% 8%
unrestricted fixef alleles-independent 80% 11% 8% 27% 11% 9%
macroareas none tone 0% 43% 2% 7% 52% 0%
macroareas none alleles-together 46% 8% 7% 41% 8% 28%
macroareas none alleles-independent 46% 6% 7% 41% 7% 28%
macroareas fixef tone 0% 6% 5% 15% 5% 1%
macroareas fixef alleles-together 79% 9% 7% 37% 9% 21%
macroareas fixef alleles-independent 79% 10% 10% 35% 9% 21%
families none tone 82% 9% 5% 44% 10% 24%
families none alleles-together 49% 6% 6% 42% 6% 16%
families none alleles-independent 52% 7% 7% 48% 6% 20%
families fixef tone 87% 6% 7% 53% 5% 25%
families fixef alleles-together 87% 12% 7% 38% 13% 18%
families fixef alleles-independent 88% 13% 9% 42% 12% 21%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 195.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 99.7% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -76.7, mean = -0.49, *p* = 0), 99.8%, when controlling for the macroarea (*t*(999) = -76.3, mean = -0.77, *p* = 0), and 99.7% when controlling for both macroarea and *MCPH1* (*t*(999) = -73.9, mean = -0.90, *p* = 0). For *MCPH1*-D (right): 73.3% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -29.3, mean = -0.24, *p* = 7.1e-137), 18.8% when controlling for the macroarea (*t*(999) = 28.6, mean = 0.91, *p* = 1), and 14.9% when controlling for both macroarea and *ASPM* (*t*(999) = 31.5, mean = 1.19, *p* = 1)._

Figure 195. Results for 1000 restricted samplings. For ASPM-D (left): 99.7% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -76.7, mean = -0.49, p = 0), 99.8%, when controlling for the macroarea (t(999) = -76.3, mean = -0.77, p = 0), and 99.7% when controlling for both macroarea and MCPH1 (t(999) = -73.9, mean = -0.90, p = 0). For MCPH1-D (right): 73.3% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -29.3, mean = -0.24, p = 7.1e-137), 18.8% when controlling for the macroarea (t(999) = 28.6, mean = 0.91, p = 1), and 14.9% when controlling for both macroarea and ASPM (t(999) = 31.5, mean = 1.19, p = 1).

brms

  • ASPM only:
    • β = -1.54, 89%HDI = [-4.00, 0.73]
    • posterior probability p(β<0) = 0.87 (evidence ratio = 6.6), p(β=0) = 0.59 (evidence ratio = 1.4)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 7.4%; pROPE = 0.066
    • comparison ‘null’ vs ‘ASPM’: [B= L= W<(27%:73%) K=]: anecdotal evidence for null against ASPM (BF=1.04), LOO=-0.73 [SE=0.83], WAIC=-0.98 [SE=0.61], KFOLD=0.18 [SE=1.19]
    • comparison ‘null’ vs ‘ASPM’: [B= L= W<(27%:73%) K=]: anecdotal evidence for null against ASPM (BF=1.04), LOO=-0.73 [SE=0.83], WAIC=-0.98 [SE=0.61], KFOLD=0.18 [SE=1.19]
  • MCPH1 only:
    • β = -1.14, 89%HDI = [-2.96, 0.90]
    • posterior probability p(β<0) = 0.84 (evidence ratio = 5.4), p(β=0) = 0.64 (evidence ratio = 1.8)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 8.3%; pROPE = 0.074
    • comparison ‘null’ vs ‘MCPH1’: [B= L< W<(30%:70%) K<]: anecdotal evidence for null against MCPH1 (BF=1.47), LOO=-1.02 [SE=0.99], WAIC=-0.86 [SE=0.58], KFOLD=-2.71 [SE=1.77]
    • comparison ‘null’ vs ‘MCPH1’: [B= L< W<(30%:70%) K<]: anecdotal evidence for null against MCPH1 (BF=1.47), LOO=-1.02 [SE=0.99], WAIC=-0.86 [SE=0.58], KFOLD=-2.71 [SE=1.77]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B= L< W<<(11%:89%) K<]: anecdotal evidence for null against both (BF=2.2), LOO=-1.21 [SE=0.96], WAIC=-2.12 [SE=0.73], KFOLD=-2.65 [SE=1.67]
    • interaction:
      • posterior probability p(=0) = 0.68 (evidence ratio = 2.1)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 10.1%; pROPE = 0.09
      • comparison ‘no interaction’ vs ‘with interaction’: [B= L= W<(41%:59%) K=]: anecdotal evidence for no interaction against with interaction (BF=1.83), LOO=-0.03 [SE=0.55], WAIC=-0.34 [SE=0.23], KFOLD=0.69 [SE=0.86]
    • ASPM (partial):
      • β = -1.32, 89%HDI = [-3.80, 1.15]
      • posterior probability p(β<0) = 0.81 (evidence ratio = 4.3), p(β=0) = 0.62 (evidence ratio = 1.6)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 7.6%; pROPE = 0.068
    • MCPH1 (partial):
      • β = -0.96, 89%HDI = [-2.92, 1.13]
      • posterior probability p(β<0) = 0.79 (evidence ratio = 3.7), p(β=0) = 0.68 (evidence ratio = 2.1)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 10.6%; pROPE = 0.094
***Figure 196.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 196.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 196. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 197.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 197.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 197. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 198.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 198.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 198. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 199.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 199.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 199. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Mediation and path analysis

Mediation analysis

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 0.32 (0.09, 0.57), p=0.004, decomposed into:

  • average direct effect (ADE): 0.14 (-0.07, 0.40), p=0.23, and

  • average indirect effect (ACME) mediated by ASPM-D: 0.19 (0.03, 0.37), p=0.004, mediating 58.1% (12.2%, 158.4%), p=0.008 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.34 ±0.26, p=8.8e-07, and
    • effect of ASPM-D on tone: -0.92 ±0.38, p=0.016.

For MCPH1-D:

  • TE: 0.32 (0.09, 0.57), p=0, decomposed into:

  • ADE: 0.36 (-0.11, 0.70), p=0.13, and

  • ACME: -0.04 (-0.32, 0.36), p=0.74, mediating -21.2% (-179.3%, 161.8%), p=0.74 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.56 ±0.16, p=7e-31, and
    • effect of MCPH1-D on tone: 0.22 ±0.53, p=0.68.
Restricted sampling
***Figure 200.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM*-D and *MCPH1*-D; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted)._

Figure 200. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM-D and MCPH1-D; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (solid), 0.05 (dashed) and 0.10 (dotted).

For ASPM-D:

  • TE: mean = 0.22, median = 0.23; 2.9% significant at α-level 0.05 and 15.2% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 61.3, p = 0;

  • ADE: mean = 0.17, median = 0.18; 0.1% significant at α-level 0.05 and 3.7% significant at α-level 0.10; 95.8% > 0.0; one-sample one-sided t-test vs 0: t(999) = 52.2, p = 9e-288;

  • ACME: mean = 0.043, median = 0.042; 0.0% significant at α-level 0.05 and 0.0% significant at α-level 0.10; 99.8% > 0.0; one-sample one-sided t-test vs 0: t(999) = 72.0, p = 0;

  • β(Africa → allele): mean = -0.74, median = -0.74; 9.7% significant at α-level 0.05 and 65.4% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -319.7, p = 0;

  • β(allele → tone | Africa): mean = -0.35, median = -0.35; 0.0% significant at α-level 0.05 and 0.0% significant at α-level 0.10; 99.6% < 0.0; one-sample one-sided t-test vs 0: t(999) = -81.0, p = 0.

For MCPH1-D:

  • TE: mean = 0.22, median = 0.23; 2.8% significant at α-level 0.05 and 14.9% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 61.3, p = 0;

  • ADE: mean = 0.33, median = 0.34; 0.0% significant at α-level 0.05 and 2.5% significant at α-level 0.10; 99.3% > 0.0; one-sample one-sided t-test vs 0: t(999) = 82.5, p = 0;

  • ACME: mean = -0.11, median = -0.12; 0.0% significant at α-level 0.05 and 0.9% significant at α-level 0.10; 19.1% > 0.0; one-sample one-sided t-test vs 0: t(999) = -28.4, p = 1;

  • β(Africa → allele): mean = -2.6, median = -2.6; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -725.0, p = 0;

  • β(allele → tone | Africa): mean = 0.7, median = 0.66; 0.0% significant at α-level 0.05 and 0.6% significant at α-level 0.10; 10.7% < 0.0; one-sample one-sided t-test vs 0: t(999) = 37.7, p = 1.

Given the low sample size N = 30 unique families, relatively few effect sizes are big enough to be significant for each individual analysis; however, there are many more significant ACMEs for ASPM-D than for MCPH1-D: 0.0% vs 0.0% (NaN times) for α-level 0.05, and 0.0% vs 0.6% (0.0 times) for α-level 0.10.

brms

Figure 201. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 202. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 203. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

All data

With Africa and tone1 coded numerically, the model fit is: χ2(1)=0.14, p=0.71; CFI=1.00, TLI=1.03, NNFI=1.03 and RFI=1.00:

Figure 204. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as numeric binary (tone_complex_num with Yes=1 and Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Likewise, with Africa and tone1 coded as ordered binary factors, the model fit is: χ2(1)=0.43, p=0.51; CFI=1.00, TLI=1.69, NNFI=1.69 and RFI=0.77:

Figure 205. Path analysis model with standardised coefficients and significance stars. tone1 and macroarea (Africa vs non-Africa) are coded as ordered binary factors (tone_complex_ord with No < Yes, and Africa_ord with outside Africa < in Africa); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D.

Restricted sampling
***Figure 206.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 206. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

  • models fits:

    • 84.6% of the p-values are not significant
    • mean(CFI) = 0.98, median(CFI) = 0.99, sd(CFI) = 0.03, IQR(CFI) = 0.03
    • mean(TLI) = 0.9, median(TLI) = 0.94, sd(TLI) = 0.2, IQR(TLI) = 0.27
    • mean(NNFI) = 0.9, median(NNFI) = 0.94, sd(NNFI) = 0.2, IQR(NNFI) = 0.27
    • mean(RFI) = 0.81, median(RFI) = 0.84, sd(RFI) = 0.17, IQR(RFI) = 0.22
  • Africa → ASPM-D: mean = -0.73, median = -0.74, sd = 0.072, IQR = 0.096, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -3.2e+02, p = 0;

  • Africa → MCPH1-D: mean = -2.6, median = -2.6, sd = 0.11, IQR = 0.16, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -7.3e+02, p = 0;

  • Africa → tone1: mean = 0.36, median = 0.37, sd = 0.22, IQR = 0.29, 95.1% > 0; 3.7% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 53, p = 1.7e-293;

  • ASPM-D → tone1: mean = -0.041, median = -0.04, sd = 0.027, IQR = 0.036, 93.9% < 0; 0.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -49, p = 6.9e-266;

  • MCPH1-D → tone1: mean = 0.067, median = 0.073, as = 0.079, IQR = 0.093, 18.4% < 0; 0.1% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 27, p = 1.

Tone counts

The resulting dataset has 121 observations, distributed among 83 unique Glottolg codes in 30 families (ranging from a minimum of 1 language per family to a maximum of 36, with a mean 4 and median 1.5 languages per family) and 4 macroareas.

There are 121:95:83 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
0 2 77 4 4 87
1 2 4 5 0 11
2 9 3 0 0 12
3 1 2 0 0 3
4 0 4 1 0 5
5 0 2 0 0 2
6 0 1 0 0 1
Sum 14 93 10 4 121
***Figure 207.*** _Distribution of tone *counts*._

Figure 207. Distribution of tone counts.

***Figure 208.*** _Distribution of tone *counts* across the world._

Figure 208. Distribution of tone counts across the world.

***Figure 209.*** _Relationship between tone *counts* (colors) and the two alleles (frequency) by macroarea._

Figure 209. Relationship between tone counts (colors) and the two alleles (frequency) by macroarea.

Regressions

glmer

All data
  • null model: R2 = 0.0%, ICC = 100.0%
  • the Poisson model is not overdispersed: χ2(119) = 60.4, p = 1
  • macroarea: pmacroarea/null = 0.037
  • ASPM:
    • by itself: R2 = 4.5%, β = -0.33 ± 0.29, pASPM/null = 0.28
    • quadratic: R2 = 34.1%, βASPM2 = -0.72 ± 0.41, pASPM2/ASPM = 0.086
    • with macroarea: R2 = 82.1%, pmacroarea/ASPM = 0.061, pASPM/macroarea = 0.82
  • MCPH1:
    • by itself: R2 = 5.1%, β = -0.37 ± 0.24, pMCPH1/null = 0.12
    • quadratic: R2 = 6.0%, βMCPH12 = -0.37 ± 0.24, pMCPH12/MCPH1 = 0.38
    • with macroarea: R2 = 81.4%, pmacroarea/MCPH1 = 0.11, pMCPH1/macroarea = 0.92
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 8.6%, βASPM = -0.24 ± 0.31, pASPM/MCPH1 = 0.43, βMCPH1 = -0.32 ± 0.24, pMCPH1/ASPM = 0.17, pASPM+MCPH1/null = 0.22,
    • interaction: R2 = 8.5%, pASPM:MCPH1/ASPM+MCPH1 = 0.94
Randomization

We performed 1000 independent replications:

Regressions with randomizations for tone counts.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 22% 18% 15% 15% 7%
unrestricted none alleles-together 27% 6% 6% 6% 6% 2%
unrestricted none alleles-independent 26% 6% 6% 5% 7% 0%
unrestricted fixef tone 0% 28% 20% 34% 19% 46%
unrestricted fixef alleles-together 98% 8% 6% 30% 7% 37%
unrestricted fixef alleles-independent 98% 8% 6% 30% 8% 39%
macroareas none tone 0% 41% 22% 25% 30% 25%
macroareas none alleles-together 50% 18% 13% 26% 12% 28%
macroareas none alleles-independent 53% 17% 12% 26% 16% 31%
macroareas fixef tone 0% 35% 25% 39% 24% 42%
macroareas fixef alleles-together 98% 11% 11% 34% 8% 45%
macroareas fixef alleles-independent 98% 9% 11% 39% 8% 45%
families none tone 89% 34% 23% 62% 17% 41%
families none alleles-together 50% 22% 20% 54% 5% 19%
families none alleles-independent 58% 27% 28% 62% 10% 25%
families fixef tone 86% 11% 16% 70% 2% 48%
families fixef alleles-together 99% 11% 15% 65% 3% 37%
families fixef alleles-independent 97% 10% 14% 63% 5% 45%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 210.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 100% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -141.3, mean = -0.40, *p* = 0), 99.2%, when controlling for the macroarea (*t*(999) = -65.0, mean = -0.48, *p* = 0), and 99.3% when controlling for both macroarea and *MCPH1* (*t*(999) = -62.1, mean = -0.61, *p* = 0). For *MCPH1*-D (right): 94.4% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -52.3, mean = -0.14, *p* = 1.8e-288), 1.7% when controlling for the macroarea (*t*(999) = 60.7, mean = 0.95, *p* = 1), and 1.3% when controlling for both macroarea and *ASPM* (*t*(999) = 54.3, mean = 1.19, *p* = 1)._

Figure 210. Results for 1000 restricted samplings. For ASPM-D (left): 100% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -141.3, mean = -0.40, p = 0), 99.2%, when controlling for the macroarea (t(999) = -65.0, mean = -0.48, p = 0), and 99.3% when controlling for both macroarea and MCPH1 (t(999) = -62.1, mean = -0.61, p = 0). For MCPH1-D (right): 94.4% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -52.3, mean = -0.14, p = 1.8e-288), 1.7% when controlling for the macroarea (t(999) = 60.7, mean = 0.95, p = 1), and 1.3% when controlling for both macroarea and ASPM (t(999) = 54.3, mean = 1.19, p = 1).

brms

  • ASPM only:
    • β = -0.36, 89%HDI = [-1.06, 0.33]
    • posterior probability p(β<0) = 0.8 (evidence ratio = 3.9), p(β=0) = 0.84 (evidence ratio = 5.3)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 14.1%; pROPE = 0.126
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(64%:36%) K=]: moderate evidence for null against ASPM (BF=7.92), LOO=0.10 [SE=0.91], WAIC=0.59 [SE=0.62], KFOLD=0.09 [SE=1.48]
  • MCPH1 only:
    • β = -0.12, 89%HDI = [-0.81, 0.56]
    • posterior probability p(β<0) = 0.63 (evidence ratio = 1.7), p(β=0) = 0.88 (evidence ratio = 7.2)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 19%; pROPE = 0.169
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(55%:45%) K=]: moderate evidence for null against MCPH1 (BF=7.2), LOO=0.43 [SE=0.49], WAIC=0.20 [SE=0.31], KFOLD=0.28 [SE=1.64]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L> W>(77%:23%) K=]: very strong evidence for null against both (BF=35.1), LOO=1.24 [SE=0.86], WAIC=1.22 [SE=0.72], KFOLD=0.58 [SE=1.48]
    • interaction:
      • posterior probability p(=0) = 0.86 (evidence ratio = 6.3)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 16.2%; pROPE = 0.144
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L<< W<<(32%:68%) K=]: moderate evidence for no interaction against with interaction (BF=7.21), LOO=-1.01 [SE=0.46], WAIC=-0.77 [SE=0.26], KFOLD=0.66 [SE=0.89]
    • ASPM (partial):
      • β = -0.3, 89%HDI = [-1.01, 0.40]
      • posterior probability p(β<0) = 0.76 (evidence ratio = 3.2), p(β=0) = 0.86 (evidence ratio = 6.1)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 16.5%; pROPE = 0.147
    • MCPH1 (partial):
      • β = -0.07, 89%HDI = [-0.73, 0.60]
      • posterior probability p(β<0) = 0.6 (evidence ratio = 1.5), p(β=0) = 0.88 (evidence ratio = 7.4)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 20%; pROPE = 0.178
***Figure 211.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 211.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 211. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 212.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 212.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 212. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 213.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 213.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 213. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

Mediation analysis

(g)lm
All data

For ASPM-D:

  • total effect (TE) of being in Africa on tone: 1.63 (0.64, 3.36), p=0, decomposed into:

  • average direct effect (ADE): 0.43 (-0.21, 1.26), p=0.19, and

  • average indirect effect (ACME) mediated by ASPM-D: 1.20 (0.47, 2.56), p=0, mediating 73.4% (44.5%, 123.6%), p=0 of the effect, resulting from:

    • effect of being in Africa on ASPM-D: -1.34 ±0.26, p=8.8e-07, and
    • effect of ASPM-D on tone: -0.75 ±0.16, p=2e-06.

For MCPH1-D:

  • TE: 1.19 (0.53, 2.06), p=0, decomposed into:

  • ADE: 3.69 (0.97, 9.95), p=0, and

  • ACME: -2.50 (-8.35, -0.01), p=0.05, mediating -165.7% (-811.6%, -0.5%), p=0.05 of the effect, resulting from:

    • effect of being in Africa on MCPH1-D: -2.56 ±0.16, p=7e-31, and
    • effect of MCPH1-D on tone: 0.43 ±0.24, p=0.081.
Restricted sampling
***Figure 214.*** _Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for *ASPM* and *MCPH1*; the middle panels show the distribution of the *p*-values for the same effects, while the rightmost panels show the distribution of the regression slopes (*β*) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (dotted), 0.05 (solid) and 0.10 (dashed)._

Figure 214. Mediation analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost panels show the distribution of point estimates of the Total Effect (TE), the Direct Effect (ADE) and the Indirect Effect (ACME) for ASPM and MCPH1; the middle panels show the distribution of the p-values for the same effects, while the rightmost panels show the distribution of the regression slopes (β) for the two alleles, top: for the regression of the allele frequency on within vs outside Africa, and bottom: for the regression of tone on the allele while controlling for within vs outside Africa. The black vertical lines show: 0.0 (dotted), 0.05 (solid) and 0.10 (dashed).

For ASPM-D:

  • TE: mean = 1.2, median = 1.3; 44.2% significant at α-level 0.05 and 67.0% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 116.8, p = 0;

  • ADE: mean = 0.89, median = 0.9; 14.8% significant at α-level 0.05 and 32.0% significant at α-level 0.10; 99.8% > 0.0; one-sample one-sided t-test vs 0: t(999) = 86.8, p = 0;

  • ACME: mean = 0.35, median = 0.34; 0.0% significant at α-level 0.05 and 1.2% significant at α-level 0.10; 99.7% > 0.0; one-sample one-sided t-test vs 0: t(999) = 72.3, p = 0;

  • β(Africa → allele): mean = -0.73, median = -0.73; 10.3% significant at α-level 0.05 and 64.3% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -310.5, p = 0;

  • β(allele → tone | Africa): mean = -0.29, median = -0.3; 2.8% significant at α-level 0.05 and 10.2% significant at α-level 0.10; 99.8% < 0.0; one-sample one-sided t-test vs 0: t(999) = -93.0, p = 0.

For MCPH1-D:

  • TE: mean = 1.3, median = 1.3; 37.1% significant at α-level 0.05 and 61.0% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 101.0, p = 0;

  • ADE: mean = 43, median = 22; 73.6% significant at α-level 0.05 and 87.0% significant at α-level 0.10; 100.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = 23.8, p = 8.4e-100;

  • ACME: mean = -42, median = -21; 50.6% significant at α-level 0.05 and 66.2% significant at α-level 0.10; 0.0% > 0.0; one-sample one-sided t-test vs 0: t(999) = -23.1, p = 1;

  • β(Africa → allele): mean = -2.6, median = -2.6; 100.0% significant at α-level 0.05 and 100.0% significant at α-level 0.10; 100.0% < 0.0; one-sample one-sided t-test vs 0: t(999) = -720.1, p = 0;

  • β(allele → tone | Africa): mean = 0.88, median = 0.87; 50.8% significant at α-level 0.05 and 67.8% significant at α-level 0.10; 0.2% < 0.0; one-sample one-sided t-test vs 0: t(999) = 78.3, p = 1.

Given the low sample size N = 35 unique families, relatively few effect sizes are big enough to be significant; however, there are many more significant indirect effects (ACME) for ASPM-D than for MCPH1-D: 2.8% vs 50.8% (0.1 times) for α-level 0.05, and 10.2% vs 67.8% (0.2 times) for α-level 0.10.

brms

Figure 215. Graphical representation of the Bayesian mediation analysis for ASPM-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 216. Graphical representation of the Bayesian mediation analysis for MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Figure 217. Graphical representation of the Bayesian mediation analysis for both ASPM-D and MCPH1-D showing the means of the effects and the actual partial regression coefficients, with their 89% HDIs and p-ROPEs. The colors reflect the sign of the mean estimate (blue=negative, red=positive, gray=(p-ROPE >= 0.05)); solid=(0 not in the HDI), dashed=(0 is in the HDI).

Path analysis

Please note that path analysis uses a linear model (so not a Poisson one) for the tone counts; also I only use the numeric coding for Africa.

All data

Coding Africa numerically, the model fits the data very well (χ2(1)=0.14, p=0.71; CFI=1.00, TLI=1.03, NNFI=1.03 and RFI=1.00):

Figure 218. Path analysis model with standardised coefficients and significance stars. Here, macroarea (Africa vs non-Africa) is coded as numeric binary (Africa_num with in Africa=1); ASPM_z is ASPM-D and MCPH1_z is MCPH1-D..

Restricted sampling
***Figure 219.*** _Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the *p*-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted)._

Figure 219. Path analysis for 1000 restricted samples (i.e., picking one random language per family). The leftmost row of two plots shows the coefficient estimates and the p-values, respectively, for the five paths in the model (see the path plots above). The rightmost plot shows the various fit indices. The black horiontal lines show: 0.0 (solid), 0.05 (dashed) and 1.0 (dotted).

It can be seen that:

  • the models fits:

    • 85.3% of the p-values are not significant
    • mean(CFI) = 0.98, median(CFI) = 0.99, sd(CFI) = 0.03, IQR(CFI) = 0.04
    • mean(TLI) = 0.91, median(TLI) = 0.93, sd(TLI) = 0.19, IQR(TLI) = 0.28
    • mean(NNFI) = 0.91, median(NNFI) = 0.93, sd(NNFI) = 0.19, IQR(NNFI) = 0.28
    • mean(RFI) = 0.81, median(RFI) = 0.84, sd(RFI) = 0.16, IQR(RFI) = 0.23
  • Africa → ASPM-D: mean = -0.73, median = -0.73, sd = 0.07, IQR = 0.095, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -3.3e+02, p = 0

  • Africa → MCPH1-D: mean = -2.6, median = -2.6, sd = 0.12, IQR = 0.15, 100.0% < 0; 100.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -7.1e+02, p = 0

  • Africa → tone counts: mean = 2.7, median = 2.7, sd = 0.84, IQR = 1.3, 100.0% > 0; 65.4% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 1e+02, p = 0

  • ASPM-D → tone counts: mean = -0.17, median = -0.17, sd = 0.12, IQR = 0.16, 92.2% < 0; 0.0% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = -46, p = 2.5e-251

  • MCPH1-D → tone counts: mean = 0.68, median = 0.68, as = 0.28, IQR = 0.38, 0.8% < 0; 36.1% significant at α-level 0.05; one-sample one-sided t-test vs 0: t(999) = 76, p = 1

Appendix V: Alternative agreement coding of tone

The explicit hierarchy of the sources for tone as used in the paper is:

  • for binary and 3-way: LAPSyD > WALS > DL2007 > WPHON > PHOIBLE, and
  • for counts: LAPSyD > WPHON > PHOIBLE

but there can be other justified choices; among these choices, I test here the alternative hierarchy:

  • for binary and 3-way: WALS > WPHON > LAPSyD > DL2007 > PHOIBLE, and
  • for counts: WPHON > LaPSyD > PHOIBLE.

The “corrected” counts are computed as LAPSyDcorr = 0.074 +1.256LAPSyD -0.11LAPSyD2, and PHOIBLEcorr = 0.415 +0.815PHOIBLE -0.049PHOIBLE2, respectively.

Relationship between alternative and main agreement codings

Binary classification

  No Yes
No 2527 14
Yes 13 1244
***Figure 220.*** _Relationship between the agreement and the `alternative' agreement codings for the binary classification._

Figure 220. Relationship between the agreement and the `alternative’ agreement codings for the binary classification.

Pearson’s Chi-squared test with Yates’ continuity correction: cooc_tab
Test statistic df P value
3673 1 0 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
3677 NA 9.999e-05 * * *

The disagreements are:

The 27 languages for which the original and the alternative binary codings disagree
glottocode PHOIBLE WALS LAPSyD LAPSyD (#) DL2007 WPHON agreement (orig) decision (orig) agreement (alt) decision (alt)
amah1246 0 NA None 0 NA 1 No LAPSyD Yes WPHON
beja1238 0 Simple None 0 NA 1 No LAPSyD + WALS, LAPSyD winns except when WALS says Complex Yes WALS
broo1239 NA NA None 0 NA 1 No LAPSyD Yes WPHON
chua1250 0 NA None 0 NA 3 No LAPSyD Yes WPHON
cofa1242 0 NA None 0 NA 1 No LAPSyD Yes WPHON
fuln1247 0 Simple None 0 NA 0 No LAPSyD + WALS, LAPSyD winns except when WALS says Complex Yes WALS
gras1249 0 Simple None 0 NA 1 No LAPSyD + WALS, LAPSyD winns except when WALS says Complex Yes WALS
hopi1249 0 Simple None 0 NA 1 No LAPSyD + WALS, LAPSyD winns except when WALS says Complex Yes WALS
mand1446 NA NA None 0 NA 1 No LAPSyD Yes WPHON
meri1244 NA NA None 0 NA 1 No LAPSyD Yes WPHON
naas1242 0 NA None 0 No 1 No LAPSyD + Dediu & Ladd, Dediu & Ladd winns except when LAPSyD says Moderately complex or Complex Yes WPHON
sapu1248 NA NA None 0 NA 1 No LAPSyD Yes WPHON
sout2982 0 NA None 0 NA 1 No LAPSyD Yes WPHON
wano1243 NA NA None 0 NA 1 No LAPSyD Yes WPHON
bora1263 0 NA Simple 1 NA 0 Yes LAPSyD No WPHON
brib1243 0 NA Simple 1 NA 0 Yes LAPSyD No WPHON
buru1296 2 None NA NA Yes 0 Yes WALS + Dediu & Ladd, Dediu & Ladd winns except when WALS says Complex No WALS
chim1309 0 NA Simple 1 NA 0 Yes LAPSyD No WPHON
darf1239 0 None Simple 1 NA 2 Yes LAPSyD + WALS, LAPSyD winns except when WALS says Complex No WALS
lepc1244 0 NA Simple 1 NA 0 Yes LAPSyD No WPHON
lith1251 0 NA Simple 1 NA 0 Yes LAPSyD No WPHON
mund1330 1 NA Simple 1 NA 0 Yes LAPSyD No WPHON
scot1245 0 NA Simple 1 NA 0 Yes LAPSyD No WPHON
sene1264 0 None Simple 1 NA 1 Yes LAPSyD + WALS, LAPSyD winns except when WALS says Complex No WALS
shek1245 NA NA Complex 8 NA 0 Yes LAPSyD No WPHON
wich1260 0 None Simple 1 NA 1 Yes LAPSyD + WALS, LAPSyD winns except when WALS says Complex No WALS
yuru1263 0 NA Simple 1 NA 0 Yes LAPSyD No WPHON

3-way classification

  None Simple Complex
None 2523 14 1
Simple 11 922 3
Complex 1 21 289
***Figure 221.*** _Relationship between the agreement and the `alternative' agreement codings for the 3-way classification._

Figure 221. Relationship between the agreement and the `alternative’ agreement codings for the 3-way classification.

Pearson’s Chi-squared test: cooc_tab
Test statistic df P value
7027 4 0 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
7027 NA 9.999e-05 * * *

The disagreements are:

The 51 languages for which the original and the alternative 3-way codings disagree
glottocode PHOIBLE WALS LAPSyD LAPSyD (#) DL2007 WPHON agreement (orig) decision (orig) agreement (alt) decision (alt)
amah1246 0 NA None 0 NA 1 None LAPSyD Simple WPHON
beja1238 0 Simple None 0 NA 1 None LAPSyD + WALS, LAPSyD winns except for Moderately complex Simple WALS
broo1239 NA NA None 0 NA 1 None LAPSyD Simple WPHON
chua1250 0 NA None 0 NA 3 None LAPSyD Simple WPHON
cofa1242 0 NA None 0 NA 1 None LAPSyD Simple WPHON
fuln1247 0 Simple None 0 NA 0 None LAPSyD + WALS, LAPSyD winns except for Moderately complex Simple WALS
gras1249 0 Simple None 0 NA 1 None LAPSyD + WALS, LAPSyD winns except for Moderately complex Simple WALS
hopi1249 0 Simple None 0 NA 1 None LAPSyD + WALS, LAPSyD winns except for Moderately complex Simple WALS
mand1446 NA NA None 0 NA 1 None LAPSyD Simple WPHON
meri1244 NA NA None 0 NA 1 None LAPSyD Simple WPHON
naas1242 0 NA None 0 No 1 None LAPSyD wins Simple WPHON
sapu1248 NA NA None 0 NA 1 None LAPSyD Simple WPHON
sout2982 0 NA None 0 NA 1 None LAPSyD Simple WPHON
wano1243 NA NA None 0 NA 1 None LAPSyD Simple WPHON
ndut1239 0 Complex None 0 NA 0 None LAPSyD + WALS, LAPSyD winns except for Moderately complex Complex WALS
bora1263 0 NA Simple 1 NA 0 Simple LAPSyD None WPHON
brib1243 0 NA Simple 1 NA 0 Simple LAPSyD None WPHON
chim1309 0 NA Simple 1 NA 0 Simple LAPSyD None WPHON
darf1239 0 None Simple 1 NA 2 Simple LAPSyD + WALS, LAPSyD winns except for Moderately complex None WALS
lepc1244 0 NA Simple 1 NA 0 Simple LAPSyD None WPHON
lith1251 0 NA Simple 1 NA 0 Simple LAPSyD None WPHON
mund1330 1 NA Simple 1 NA 0 Simple LAPSyD None WPHON
scot1245 0 NA Simple 1 NA 0 Simple LAPSyD None WPHON
sene1264 0 None Simple 1 NA 1 Simple LAPSyD + WALS, LAPSyD winns except for Moderately complex None WALS
wich1260 0 None Simple 1 NA 1 Simple LAPSyD + WALS, LAPSyD winns except for Moderately complex None WALS
yuru1263 0 NA Simple 1 NA 0 Simple LAPSyD None WPHON
east2652 1 Complex Simple 1 NA 1 Simple LAPSyD + WALS, LAPSyD winns except for Moderately complex Complex WALS
nort2740 0 NA Simple 1 NA 4 Simple LAPSyD Complex WPHON
vani1248 0 Complex Simple 1 NA 2 Simple LAPSyD + WALS, LAPSyD winns except for Moderately complex Complex WALS
shek1245 NA NA Complex 8 NA 0 Complex LAPSyD None WPHON
abun1252 NA NA Moderately complex 2 NA 1 Complex LAPSyD Simple WPHON
bamu1253 0 NA NA NA Yes 3 Complex From n_tones Simple WPHON
bass1258 NA NA Moderately complex 3 NA 2 Complex LAPSyD Simple WPHON
cacu1241 0 Simple Complex 3 NA 3 Complex LAPSyD + WALS, LAPSyD winns except for Moderately complex Simple WALS
cent2144 2 NA Complex 3 NA 2 Complex LAPSyD Simple WPHON
diga1241 NA NA Complex 3 NA 3 Complex LAPSyD Simple WPHON
gaam1241 2 Simple Complex 3 NA 1 Complex LAPSyD + WALS, LAPSyD winns except for Moderately complex Simple WALS
hlai1239 NA NA Moderately complex 2 NA 3 Complex LAPSyD Simple WPHON
jeme1245 0 NA Moderately complex 2 NA 3 Complex LAPSyD Simple WPHON
jica1244 2 NA Moderately complex 2 NA 1 Complex LAPSyD Simple WPHON
kala1373 NA Simple Complex 4 NA 1 Complex LAPSyD + WALS, LAPSyD winns except for Moderately complex Simple WALS
kris1246 3 NA Complex 3 NA 3 Complex LAPSyD Simple WPHON
lele1276 2 NA Moderately complex 2 NA 2 Complex LAPSyD Simple WPHON
madi1260 3 NA Moderately complex 2 Yes 2 Complex LAPSyD wins Simple WPHON
nort2732 NA NA NA NA Yes 3 Complex From n_tones Simple WPHON
nucl1620 0 NA Moderately complex 2 NA 2 Complex LAPSyD Simple WPHON
puin1248 0 NA Complex 3 NA 1 Complex LAPSyD Simple WPHON
sand1273 4 Simple Complex 3 Yes 2 Complex LAPSyD wins Simple WALS
xhos1239 1 NA NA NA Yes 2 Complex From n_tones Simple WPHON
yaka1272 NA NA NA NA Yes 2 Complex From n_tones Simple WPHON
yuhu1238 0 NA Complex 3 NA 1 Complex LAPSyD Simple WPHON

Counts

***Figure 222.*** _Relationship between the agreement and the `alternative' agreement codings for the counts._

Figure 222. Relationship between the agreement and the `alternative’ agreement codings for the counts.

Pearson’s product-moment correlation: agreement and agreement_alt
Test statistic df P value Alternative hypothesis cor
164.8 3783 0 * * * two.sided 0.9369
Spearman’s rank correlation rho: agreement and agreement_alt
Test statistic P value Alternative hypothesis rho
193189299 0 * * * two.sided 0.9786

Look at the serious disagreements (i.e., more than 1):

The 59 languages for which the original and the alternative count codings disagree, ordered by their absolute difference
glottocode PHOIBLE WALS LAPSyD LAPSyD (#) DL2007 WPHON agreement (orig) agreement (alt) difference (abs)
achu1247 0 Simple Simple 1 NA 3 1 3 2
anga1290 0 Simple Moderately complex 2 NA 0 2 0 2
awng1244 6 Simple Simple 1 NA 3 1 3 2
cent2050 3 Simple Simple 1 NA 3 1 3 2
efik1245 0 Simple Moderately complex 2 NA 4 2 4 2
gaam1241 2 Simple Complex 3 NA 1 3 1 2
gads1258 3 Complex Complex 3 NA 1 3 1 2
hmon1333 NA NA NA NA NA 7 5 7 2
iumi1238 3 Complex NA NA NA 7 5 7 2
kera1255 0 Complex Moderately complex 2 NA 0 2 0 2
komc1235 6 NA NA NA NA 7 5 7 2
koro1298 NA None None 0 NA 2 0 2 2
koyr1240 5 None None 0 NA 2 0 2 2
kuta1241 NA NA NA NA NA 6 4 6 2
lamn1239 6 NA NA NA NA 7 5 7 2
larg1235 NA NA NA NA NA 6 4 6 2
mind1253 0 Complex NA NA NA 7 5 7 2
mruu1242 NA NA NA NA NA 7 5 7 2
murl1244 0 Simple Simple 2 NA 4 2 4 2
nama1264 0 Complex Complex 5 Yes 3 5 3 2
ncan1245 5 NA NA NA NA 6 4 6 2
ngba1285 0 NA NA NA NA 6 4 6 2
nort2747 NA NA NA NA NA 7 5 7 2
nort2819 2 Complex NA NA NA 6 4 6 2
nucl1649 0 None None 0 NA 2 0 2 2
nucl1770 NA NA NA NA NA 7 5 7 2
nung1283 0 Complex Complex 5 NA 3 5 3 2
pira1253 0 Simple Simple 1 NA 3 1 3 2
puin1248 0 NA Complex 3 NA 1 3 1 2
puxi1243 NA NA NA NA NA 6 4 6 2
pwon1235 4 Complex Complex 3 NA 5 3 5 2
smal1236 NA NA NA NA NA 7 5 7 2
sout2741 NA NA NA NA NA 6 4 6 2
sout2754 NA NA NA NA NA 7 5 7 2
sout2844 0 NA NA NA NA 6 4 6 2
tain1252 0 NA NA NA Yes 6 4 6 2
thak1245 0 NA Simple 1 NA 3 1 3 2
timn1235 3 Simple Simple 1 NA 3 1 3 2
veng1238 8 NA NA NA NA 7 5 7 2
yako1252 NA NA NA NA NA 6 4 6 2
youn1235 NA NA NA NA NA 7 5 7 2
yuhu1238 0 NA Complex 3 NA 1 3 1 2
bero1242 0 Complex Complex 6 NA 3 6 3 3
chua1250 0 NA None 0 NA 3 0 3 3
kala1373 NA Simple Complex 4 NA 1 4 1 3
lada1244 0 None None 0 NA 3 0 3 3
mmen1238 4 NA NA NA NA 8 5 8 3
nige1255 1 Complex NA NA NA 8 5 8 3
nort2740 0 NA Simple 1 NA 4 1 4 3
ticu1245 8 Complex Complex 4 NA 7 4 7 3
aghe1239 1 Simple Simple 1 NA 5 1 5 4
cent1394 NA NA Complex 3 NA 7 3 7 4
ejag1239 4 Complex Complex 5 NA 1 5 1 4
monz1249 NA NA NA NA NA 9 5 9 4
gban1258 NA NA NA NA NA 10 5 10 5
vute1244 4 NA NA NA NA 10 5 10 5
niel1243 2 Complex NA NA NA 11 5 11 6
mali1285 NA NA Complex 10 NA NA 10 2 8
shek1245 NA NA Complex 8 NA 0 8 0 8

Conclusion

So, the “original” and the “alternative” codings agree rather well…

Stats

Here, I re-do that stats using the “alternative” coding.

tone1

There are 181 observations, distributed among 119 unique Glottolg codes in 35 families (ranging from a minimum of 1 language per family to a maximum of 48, with a mean 5.2 and median 2 languages per family) and 4 macroareas.

There are 161:126:119 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 9 101 4 6 120
Yes 27 25 6 3 61
Sum 36 126 10 9 181
***Figure 223.*** _Distribution of *tone1*._

Figure 223. Distribution of tone1.

***Figure 224.*** _Map of *tone1*._

Figure 224. Map of tone1.

***Figure 225.*** _Relationship between *tone1*, *ASPM*-D and *MCPH1*-D._

Figure 225. Relationship between tone1, ASPM-D and MCPH1-D.

The agreement with the original tone1 coding is extremely high:

  No Yes
No 119 1
Yes 1 60
***Figure 226.*** _Relationship between the agreement and the `alternative' agreement codings for *tone1*._

Figure 226. Relationship between the agreement and the `alternative’ agreement codings for tone1.

Pearson’s Chi-squared test with Yates’ continuity correction: cooc_tab
Test statistic df P value
167.8 1 2.212e-38 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
172.2 NA 9.999e-05 * * *

The disagreements are:

The 2 languages for which the original and the alternative tone1 disagree
glottocode Pop_ID metapopulation family macroarea original alternative
naas1242 SA002261L Melanesian_Nasioi South Bougainville Papunesia No Yes
buru1296 SA001482P Burusho Burushaski Eurasia Yes No

so I expect the results of the analysis to be virtually identical…

tone2

The resulting dataset has 180 observations, distributed among 118 unique Glottolg codes in 35 families (ranging from a minimum of 1 language per family to a maximum of 47, with a mean 5.1 and median 2 languages per family) and 4 macroareas.

There are 156:121:118 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 31 106 9 9 155
Yes 6 17 1 1 25
Sum 37 123 10 10 180
***Figure 227.*** _Distribution of *tone2*._

Figure 227. Distribution of tone2.

***Figure 228.*** _Map of *tone2*._

Figure 228. Map of tone2.

***Figure 229.*** _Relationship between *tone2*, *ASPM*-D and *MCPH1*-D._

Figure 229. Relationship between tone2, ASPM-D and MCPH1-D.

The agreement with the original tone2 coding is extremely high:

  No Yes
No 151 0
Yes 4 25
***Figure 230.*** _Relationship between the agreement and the `alternative' agreement codings for *tone2*._

Figure 230. Relationship between the agreement and the `alternative’ agreement codings for tone2.

Pearson’s Chi-squared test with Yates’ continuity correction: cooc_tab
Test statistic df P value
144 1 3.472e-33 * * *
Pearson’s Chi-squared test with simulated p-value (based on 10000 replicates): cooc_tab
Test statistic df P value
151.2 NA 9.999e-05 * * *

The disagreements are:

The 4 languages for which the original and the alternative tone2 disagree
glottocode Pop_ID metapopulation family macroarea original alternative
bamu1253 MB2005_Bamoun Bamoun Atlantic-Congo Africa Yes No
sand1273 SA004366T Sandawe Sandawe Africa Yes No
nort2732 SA001484R Tujia Sino-Tibetan Eurasia Yes No
yaka1272 SA002256P Biaka Atlantic-Congo Africa Yes No

so I expect the results of the analysis to be very similar…

Tone counts

The resulting dataset has 183 observations, distributed among 120 unique Glottolg codes in 35 families (ranging from a minimum of 1 language per family to a maximum of 47, with a mean 5.2 and median 2 languages per family) and 4 macroareas.

There are 156:121:120 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
0 9 97 4 6 116
1 9 7 5 2 23
2 15 1 0 1 17
3 4 5 0 1 10
4 1 3 0 0 4
5 0 8 0 0 8
6 0 3 0 0 3
7 0 1 1 0 2
Sum 38 125 10 10 183
***Figure 231.*** _Distribution of tone *counts*._

Figure 231. Distribution of tone counts.

***Figure 232.*** _Distribution of tone *counts* across the world._

Figure 232. Distribution of tone counts across the world.

***Figure 233.*** _Relationship between tone *counts* (colors) and the two alleles (frequency) by macroarea._

Figure 233. Relationship between tone counts (colors) and the two alleles (frequency) by macroarea.

The original and alternative tone counts are very similar:

***Figure 234.*** _Relationship between the agreement and the `alternative' agreement for tone *counts*._

Figure 234. Relationship between the agreement and the `alternative’ agreement for tone counts.

Pearson’s product-moment correlation: n_tones_orig and n_tones_alt
Test statistic df P value Alternative hypothesis cor
38.96 181 6.161e-90 * * * two.sided 0.9452
Spearman’s rank correlation rho: n_tones_orig and n_tones_alt
Test statistic P value Alternative hypothesis rho
17364 3.499e-135 * * * two.sided 0.983

Look at the serious disagreements (i.e., more than 1):

The 6 languages for which the original and the alternative tone counts disagree by more than 1
glottocode Pop_ID metapopulation family macroarea original alternative difference
awng1244 SA004368V Jews_Ethiopian Afro-Asiatic Africa 1 3 2
nama1264 SA001469U San Khoe-Kwadi Africa 5 3 2
tain1252 SA001493R Dai Tai-Kadai Eurasia 4 6 2
tain1252 SA004238R Dai Tai-Kadai Eurasia 4 6 2
ticu1245 SA004389Y Ticuna Ticuna-Yuri America 4 7 3
cent1394 SA001486T Miao Hmong-Mien Eurasia 3 7 4

so I expect the results of the analysis to be very similar…

Appendix IV: Macroareas as units of analysis

Excluding Africa

Here I exclude from the analysis all the African data points.

tone1

There are 145 observations, distributed among 89 unique Glottolg codes in 28 families (ranging from a minimum of 1 language per family to a maximum of 48, with a mean 5.2 and median 2 languages per family) and 3 macroareas.

There are 134:102:89 unique samples:(meta)populations:languages retained.

  America Eurasia Papunesia Sum
No 4 100 7 111
Yes 6 26 2 34
Sum 10 126 9 145
***Figure 235.*** _Distribution of *tone1*._

Figure 235. Distribution of tone1.

***Figure 236.*** _Map of *tone1*._

Figure 236. Map of tone1.

***Figure 237.*** _Relationship between *tone1*, *ASPM*-D and *MCPH1*-D._

Figure 237. Relationship between tone1, ASPM-D and MCPH1-D.

Regressions

glmer
All data
  • null model: R2 = 0.0%, ICC = 85.6%
  • macroarea: pmacroarea/null = 0.2
  • ASPM:
    • by itself: R2 = 0.3%, β = -0.23 ± 0.52, pASPM/null = 0.67
    • quadratic: R2 = 1.6%, βASPM2 = -0.14 ± 0.72, pASPM2/ASPM = 0.28
    • with macroarea: R2 = 9.2%, pmacroarea/ASPM = 0.2, pASPM/macroarea = 0.71
  • MCPH1:
    • by itself: R2 = 0.0%, β = 0.11 ± 0.42, pMCPH1/null = 0.8
    • quadratic: R2 = 0.7%, βMCPH12 = 0.07 ± 0.48, pMCPH12/MCPH1 = 0.18
    • with macroarea: R2 = 9.3%, pmacroarea/MCPH1 = 0.2, pMCPH1/macroarea = 0.91
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 0.7%, βASPM = -0.30 ± 0.54, pASPM/MCPH1 = 0.59, βMCPH1 = 0.17 ± 0.41, pMCPH1/ASPM = 0.67, pASPM+MCPH1/null = 0.83,
    • interaction: R2 = 2.1%, pASPM:MCPH1/ASPM+MCPH1 = 0.27
Randomization

I performed 1000 independent replications of each of these parameter combinations, and below are the distributions of the permuted values versus the original ones (i.e., those obtained on the original, non-permuted data).

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 4% 4% 6% 5% 79%
unrestricted none alleles-together 85% 7% 7% 22% 8% 64%
unrestricted none alleles-independent 84% 7% 7% 22% 6% 64%
unrestricted fixef tone 0% 5% 4% 84% 5% 45%
unrestricted fixef alleles-together 93% 9% 9% 66% 7% 46%
unrestricted fixef alleles-independent 94% 6% 6% 70% 6% 46%
macroareas none tone 0% 19% 15% 33% 13% 47%
macroareas none alleles-together 87% 7% 7% 36% 7% 52%
macroareas none alleles-independent 87% 8% 7% 36% 9% 51%
macroareas fixef tone 0% 5% 6% 82% 6% 47%
macroareas fixef alleles-together 94% 7% 7% 65% 6% 46%
macroareas fixef alleles-independent 93% 7% 7% 69% 6% 48%
families none tone 88% 6% 7% 49% 3% 53%
families none alleles-together 91% 9% 10% 62% 5% 44%
families none alleles-independent 90% 9% 10% 57% 6% 55%
families fixef tone 81% 5% 5% 73% 2% 38%
families fixef alleles-together 93% 6% 7% 78% 3% 37%
families fixef alleles-independent 92% 5% 6% 75% 5% 47%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 238.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 99.9% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -66.0, mean = -0.71, *p* = 0), 95.2%, when controlling for the macroarea (*t*(999) = -42.2, mean = -0.65, *p* = 1.2e-224), and 95.5% when controlling for both macroarea and *MCPH1* (*t*(999) = -33.2, mean = -0.89, *p* = 8.2e-164). For *MCPH1*-D (right): 32.1% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = 15.3, mean = 0.13, *p* = 1), 87.6% when controlling for the macroarea (*t*(999) = -35.5, mean = -0.50, *p* = 1.2e-179), and 86.9% when controlling for both macroarea and *ASPM* (*t*(999) = -30.3, mean = -0.80, *p* = 6e-144)._

Figure 238. Results for 1000 restricted samplings. For ASPM-D (left): 99.9% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -66.0, mean = -0.71, p = 0), 95.2%, when controlling for the macroarea (t(999) = -42.2, mean = -0.65, p = 1.2e-224), and 95.5% when controlling for both macroarea and MCPH1 (t(999) = -33.2, mean = -0.89, p = 8.2e-164). For MCPH1-D (right): 32.1% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = 15.3, mean = 0.13, p = 1), 87.6% when controlling for the macroarea (t(999) = -35.5, mean = -0.50, p = 1.2e-179), and 86.9% when controlling for both macroarea and ASPM (t(999) = -30.3, mean = -0.80, p = 6e-144).

brms
  • ASPM only:
    • β = -0.19, 89%HDI = [-1.54, 1.17]
    • posterior probability p(β<0) = 0.6 (evidence ratio = 1.5), p(β=0) = 0.8 (evidence ratio = 4.1)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 19.9%; pROPE = 0.177
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(43%:57%) K=]: moderate evidence for null against ASPM (BF=3.3), LOO=0.23 [SE=0.70], WAIC=-0.29 [SE=0.32], KFOLD=0.74 [SE=0.91]
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(43%:57%) K=]: moderate evidence for null against ASPM (BF=3.3), LOO=0.23 [SE=0.70], WAIC=-0.29 [SE=0.32], KFOLD=0.74 [SE=0.91]
  • MCPH1 only:
    • β = 0.32, 89%HDI = [-0.76, 1.62]
    • posterior probability p(β<0) = 0.35 (evidence ratio = 0.54), p(β=0) = 0.81 (evidence ratio = 4.2)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 21.5%; pROPE = 0.191
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W<(33%:67%) K>]: moderate evidence for null against MCPH1 (BF=3.79), LOO=-0.58 [SE=0.74], WAIC=-0.69 [SE=0.36], KFOLD=2.03 [SE=1.93]
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W<(33%:67%) K>]: moderate evidence for null against MCPH1 (BF=3.79), LOO=-0.58 [SE=0.74], WAIC=-0.69 [SE=0.36], KFOLD=2.03 [SE=1.93]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L> W=(37%:63%) K=]: strong evidence for null against both (BF=10.8), LOO=1.02 [SE=0.89], WAIC=-0.53 [SE=0.56], KFOLD=-0.24 [SE=3.20]
    • interaction:
      • posterior probability p(=0) = 0.77 (evidence ratio = 3.3)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 16%; pROPE = 0.142
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L< W<(27%:73%) K>>]: moderate evidence for no interaction against with interaction (BF=4.09), LOO=-1.73 [SE=0.94], WAIC=-0.98 [SE=0.65], KFOLD=9.48 [SE=3.05]
    • ASPM (partial):
      • β = -0.16, 89%HDI = [-1.54, 1.43]
      • posterior probability p(β<0) = 0.58 (evidence ratio = 1.4), p(β=0) = 0.79 (evidence ratio = 3.7)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 18.9%; pROPE = 0.168
    • MCPH1 (partial):
      • β = 0.37, 89%HDI = [-0.90, 1.61]
      • posterior probability p(β<0) = 0.33 (evidence ratio = 0.48), p(β=0) = 0.8 (evidence ratio = 4.1)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 20.7%; pROPE = 0.184
***Figure 239.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 239.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 239. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 240.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 240.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 240. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 241.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 241.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 241. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 242.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 242.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 242. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

tone2

The resulting dataset has 143 observations, distributed among 87 unique Glottolg codes in 28 families (ranging from a minimum of 1 language per family to a maximum of 47, with a mean 5.1 and median 2 languages per family) and 3 macroareas.

There are 131:99:87 unique samples:(meta)populations:languages retained.

  America Eurasia Papunesia Sum
No 9 105 9 123
Yes 1 18 1 20
Sum 10 123 10 143
***Figure 243.*** _Distribution of *tone2*._

Figure 243. Distribution of tone2.

***Figure 244.*** _Map of *tone2*._

Figure 244. Map of tone2.

***Figure 245.*** _Relationship between *tone2*, *ASPM*-D and *MCPH1*-D._

Figure 245. Relationship between tone2, ASPM-D and MCPH1-D.

Regressions

glmer
All data
  • null model: R2 = 0.0%, ICC = 98.3%
  • macroarea: pmacroarea/null = 0.97
  • ASPM:
    • by itself: R2 = 0.1%, β = 0.35 ± 1.11, pASPM/null = 0.75
    • quadratic: R2 = 37.2%, βASPM2 = -8.33 ± 6.96, pASPM2/ASPM = 0.028
    • with macroarea: R2 = 0.1%, pmacroarea/ASPM = 0.93, pASPM/macroarea = 0.67
  • MCPH1:
    • by itself: R2 = 0.0%, β = 0.20 ± 0.96, pMCPH1/null = 0.83
    • quadratic: R2 = 1.0%, βMCPH12 = 0.07 ± 1.26, pMCPH12/MCPH1 = 0.15
    • with macroarea: R2 = 0.1%, pmacroarea/MCPH1 = 0.98, pMCPH1/macroarea = 0.87
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 0.1%, βASPM = 0.32 ± 1.12, pASPM/MCPH1 = 0.77, βMCPH1 = 0.17 ± 1.01, pMCPH1/ASPM = 0.86, pASPM+MCPH1/null = 0.94,
    • interaction: R2 = 0.2%, pASPM:MCPH1/ASPM+MCPH1 = 0.53
Randomization

I performed 1000 independent replications of each of these parameter combinations, and below are the distributions of the permuted values versus the original ones (i.e., those obtained on the original, non-permuted data).

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 6% 6% 87% 6% 72%
unrestricted none alleles-together 94% 8% 8% 65% 8% 60%
unrestricted none alleles-independent 95% 8% 8% 65% 7% 58%
unrestricted fixef tone 0% 6% 5% 96% 6% 56%
unrestricted fixef alleles-together 94% 8% 8% 74% 8% 54%
unrestricted fixef alleles-independent 94% 10% 8% 74% 9% 54%
macroareas none tone 0% 3% 4% 87% 5% 74%
macroareas none alleles-together 95% 9% 8% 70% 8% 54%
macroareas none alleles-independent 95% 10% 10% 68% 9% 58%
macroareas fixef tone 0% 6% 6% 95% 6% 53%
macroareas fixef alleles-together 93% 12% 10% 74% 11% 52%
macroareas fixef alleles-independent 92% 12% 10% 74% 10% 51%
families none tone 63% 8% 7% 77% 4% 45%
families none alleles-together 90% 6% 5% 75% 3% 45%
families none alleles-independent 89% 7% 7% 74% 6% 54%
families fixef tone 63% 8% 8% 82% 4% 34%
families fixef alleles-together 86% 6% 5% 76% 4% 40%
families fixef alleles-independent 89% 7% 9% 78% 7% 48%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 246.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 100% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -98.2, mean = -0.74, *p* = 0), 100%, when controlling for the macroarea (*t*(999) = -77.7, mean = -1.35, *p* = 0), and 100% when controlling for both macroarea and *MCPH1* (*t*(999) = -68.8, mean = -1.58, *p* = 0). For *MCPH1*-D (right): 62.1% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -9.5, mean = -0.10, *p* = 5.2e-21), 65.7% when controlling for the macroarea (*t*(999) = -12.0, mean = -0.21, *p* = 1.5e-31), and 68.7% when controlling for both macroarea and *ASPM* (*t*(999) = -14.4, mean = -0.42, *p* = 5.7e-43)._

Figure 246. Results for 1000 restricted samplings. For ASPM-D (left): 100% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -98.2, mean = -0.74, p = 0), 100%, when controlling for the macroarea (t(999) = -77.7, mean = -1.35, p = 0), and 100% when controlling for both macroarea and MCPH1 (t(999) = -68.8, mean = -1.58, p = 0). For MCPH1-D (right): 62.1% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -9.5, mean = -0.10, p = 5.2e-21), 65.7% when controlling for the macroarea (t(999) = -12.0, mean = -0.21, p = 1.5e-31), and 68.7% when controlling for both macroarea and ASPM (t(999) = -14.4, mean = -0.42, p = 5.7e-43).

brms
  • ASPM only:
    • β = -0.68, 89%HDI = [-2.49, 1.31]
    • posterior probability p(β<0) = 0.72 (evidence ratio = 2.6), p(β=0) = 0.72 (evidence ratio = 2.6)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 11.5%; pROPE = 0.102
    • comparison ‘null’ vs ‘ASPM’: [B> L> W>(65%:35%) K>]: moderate evidence for null against ASPM (BF=3.61), LOO=1.75 [SE=1.00], WAIC=0.60 [SE=0.48], KFOLD=0.72 [SE=0.65]
    • comparison ‘null’ vs ‘ASPM’: [B> L> W>(65%:35%) K>]: moderate evidence for null against ASPM (BF=3.61), LOO=1.75 [SE=1.00], WAIC=0.60 [SE=0.48], KFOLD=0.72 [SE=0.65]
  • MCPH1 only:
    • β = 0.13, 89%HDI = [-1.41, 1.84]
    • posterior probability p(β<0) = 0.46 (evidence ratio = 0.84), p(β=0) = 0.78 (evidence ratio = 3.6)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 17.9%; pROPE = 0.16
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(51%:49%) K<]: moderate evidence for null against MCPH1 (BF=3.36), LOO=-0.12 [SE=0.43], WAIC=0.03 [SE=0.31], KFOLD=-0.96 [SE=0.51]
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(51%:49%) K<]: moderate evidence for null against MCPH1 (BF=3.36), LOO=-0.12 [SE=0.43], WAIC=0.03 [SE=0.31], KFOLD=-0.96 [SE=0.51]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B> L= W=(52%:48%) K>>]: moderate evidence for null against both (BF=7.53), LOO=0.20 [SE=0.62], WAIC=0.06 [SE=0.56], KFOLD=8.34 [SE=4.00]
    • interaction:
      • posterior probability p(=0) = 0.7 (evidence ratio = 2.4)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 10.5%; pROPE = 0.094
      • comparison ‘no interaction’ vs ‘with interaction’: [B= L< W<(33%:67%) K<]: anecdotal evidence for no interaction against with interaction (BF=2.84), LOO=-0.76 [SE=0.51], WAIC=-0.69 [SE=0.35], KFOLD=-5.06 [SE=4.57]
    • ASPM (partial):
      • β = -0.68, 89%HDI = [-2.85, 1.40]
      • posterior probability p(β<0) = 0.71 (evidence ratio = 2.4), p(β=0) = 0.71 (evidence ratio = 2.4)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 11.5%; pROPE = 0.102
    • MCPH1 (partial):
      • β = 0.15, 89%HDI = [-1.44, 1.90]
      • posterior probability p(β<0) = 0.46 (evidence ratio = 0.84), p(β=0) = 0.78 (evidence ratio = 3.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 17%; pROPE = 0.152
***Figure 247.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 247.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 247. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 248.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 248.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 248. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 249.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 249.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 249. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 250.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 250.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 250. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Tone counts

The resulting dataset has 146 observations, distributed among 89 unique Glottolg codes in 28 families (ranging from a minimum of 1 language per family to a maximum of 47, with a mean 5.2 and median 2 languages per family) and 3 macroareas.

There are 131:99:89 unique samples:(meta)populations:languages retained.

  America Eurasia Papunesia Sum
0 4 98 7 109
1 5 6 1 12
2 0 3 2 5
3 0 5 0 5
4 1 8 0 9
5 0 4 0 4
6 0 2 0 2
Sum 10 126 10 146
***Figure 251.*** _Distribution of tone *counts*._

Figure 251. Distribution of tone counts.

***Figure 252.*** _Distribution of tone *counts* across the world._

Figure 252. Distribution of tone counts across the world.

***Figure 253.*** _Relationship between tone *counts* (colors) and the two alleles (frequency) by macroarea._

Figure 253. Relationship between tone counts (colors) and the two alleles (frequency) by macroarea.

Regressions

glmer
All data
  • null model: R2 = 0.0%, ICC = 100.0%
  • the Poisson model is not overdispersed: χ2(144) = 78.8, p = 1
  • macroarea: pmacroarea/null = 0.6
  • ASPM:
    • by itself: R2 = 0.0%, β = 0.00 ± 0.25, pASPM/null = 1
    • quadratic: R2 = 8.5%, βASPM2 = -0.33 ± 0.33, pASPM2/ASPM = 0.073
    • with macroarea: R2 = 2.3%, pmacroarea/ASPM = 0.58, pASPM/macroarea = 0.79
  • MCPH1:
    • by itself: R2 = 0.2%, β = -0.08 ± 0.17, pMCPH1/null = 0.63
    • quadratic: R2 = 2.0%, βMCPH12 = -0.04 ± 0.18, pMCPH12/MCPH1 = 0.16
    • with macroarea: R2 = 2.7%, pmacroarea/MCPH1 = 0.53, pMCPH1/macroarea = 0.5
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 0.2%, βASPM = -0.01 ± 0.25, pASPM/MCPH1 = 0.96, βMCPH1 = -0.08 ± 0.17, pMCPH1/ASPM = 0.63, pASPM+MCPH1/null = 0.89,
    • interaction: R2 = 0.3%, pASPM:MCPH1/ASPM+MCPH1 = 0.76
Randomization

We performed 1000 independent replications:

Regressions with randomizations for tone counts.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 35% 24% 40% 25% 35%
unrestricted none alleles-together 89% 3% 3% 43% 4% 24%
unrestricted none alleles-independent 88% 3% 4% 44% 4% 22%
unrestricted fixef tone 0% 36% 25% 56% 24% 28%
unrestricted fixef alleles-together 78% 4% 4% 68% 3% 15%
unrestricted fixef alleles-independent 74% 2% 3% 71% 3% 12%
macroareas none tone 0% 33% 20% 50% 24% 28%
macroareas none alleles-together 88% 3% 3% 54% 4% 17%
macroareas none alleles-independent 88% 3% 4% 55% 4% 17%
macroareas fixef tone 0% 35% 24% 54% 25% 28%
macroareas fixef alleles-together 77% 3% 4% 69% 3% 15%
macroareas fixef alleles-independent 76% 3% 4% 68% 4% 18%
families none tone 69% 5% 11% 79% 1% 33%
families none alleles-together 90% 6% 10% 80% 0% 23%
families none alleles-independent 88% 6% 13% 80% 1% 23%
families fixef tone 67% 5% 10% 84% 1% 23%
families fixef alleles-together 77% 7% 10% 86% 1% 22%
families fixef alleles-independent 77% 6% 11% 86% 1% 19%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 254.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 99.9% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -74.5, mean = -0.43, *p* = 0), 98.2%, when controlling for the macroarea (*t*(999) = -59.5, mean = -0.60, *p* = 0), and 98.4% when controlling for both macroarea and *MCPH1* (*t*(999) = -61.1, mean = -0.67, *p* = 0). For *MCPH1*-D (right): 35.2% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = 15.6, mean = 0.13, *p* = 1), 43.2% when controlling for the macroarea (*t*(999) = 8.4, mean = 0.11, *p* = 1), and 45.2% when controlling for both macroarea and *ASPM* (*t*(999) = 8.2, mean = 0.15, *p* = 1)._

Figure 254. Results for 1000 restricted samplings. For ASPM-D (left): 99.9% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -74.5, mean = -0.43, p = 0), 98.2%, when controlling for the macroarea (t(999) = -59.5, mean = -0.60, p = 0), and 98.4% when controlling for both macroarea and MCPH1 (t(999) = -61.1, mean = -0.67, p = 0). For MCPH1-D (right): 35.2% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = 15.6, mean = 0.13, p = 1), 43.2% when controlling for the macroarea (t(999) = 8.4, mean = 0.11, p = 1), and 45.2% when controlling for both macroarea and ASPM (t(999) = 8.2, mean = 0.15, p = 1).

brms
  • ASPM only:
    • β = -0.12, 89%HDI = [-0.64, 0.40]
    • posterior probability p(β<0) = 0.64 (evidence ratio = 1.8), p(β=0) = 0.91 (evidence ratio = 9.9)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 26.2%; pROPE = 0.233
    • comparison ‘null’ vs ‘ASPM’: [B>> L>> W>>(67%:33%) K=]: strong evidence for null against ASPM (BF=11.8), LOO=1.40 [SE=0.57], WAIC=0.71 [SE=0.33], KFOLD=-0.27 [SE=2.39]
  • MCPH1 only:
    • β = 0.01, 89%HDI = [-0.33, 0.34]
    • posterior probability p(β<0) = 0.48 (evidence ratio = 0.92), p(β=0) = 0.94 (evidence ratio = 16)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 42.3%; pROPE = 0.376
    • comparison ‘null’ vs ‘MCPH1’: [B>> L= W=(57%:43%) K=]: strong evidence for null against MCPH1 (BF=12.8), LOO=0.01 [SE=0.58], WAIC=0.28 [SE=0.29], KFOLD=-1.27 [SE=2.61]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L>> W>>(77%:23%) K=]: very strong evidence for null against both (BF=80.5), LOO=1.83 [SE=0.81], WAIC=1.20 [SE=0.49], KFOLD=1.19 [SE=2.51]
    • interaction:
      • posterior probability p(=0) = 0.92 (evidence ratio = 11)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 28.7%; pROPE = 0.255
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L= W=(45%:55%) K=]: moderate evidence for no interaction against with interaction (BF=8.41), LOO=-0.69 [SE=0.85], WAIC=-0.21 [SE=0.30], KFOLD=-0.59 [SE=1.39]
    • ASPM (partial):
      • β = -0.13, 89%HDI = [-0.67, 0.40]
      • posterior probability p(β<0) = 0.66 (evidence ratio = 1.9), p(β=0) = 0.91 (evidence ratio = 9.9)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 25.9%; pROPE = 0.231
    • MCPH1 (partial):
      • β = 0, 89%HDI = [-0.34, 0.34]
      • posterior probability p(β<0) = 0.5 (evidence ratio = 0.98), p(β=0) = 0.94 (evidence ratio = 15)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 40%; pROPE = 0.356
***Figure 255.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 255.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 255. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 256.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 256.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 256. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 257.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 257.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 257. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

Only Africa

Here I use only the African data points.

tone1

There are 36 observations, distributed among 30 unique Glottolg codes in 8 families (ranging from a minimum of 1 language per family to a maximum of 16, with a mean 4.5 and median 1.5 languages per family) and 1 macroareas.

There are 27:24:30 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 9 0 0 0 9
Yes 27 0 0 0 27
Sum 36 0 0 0 36
***Figure 258.*** _Distribution of *tone1*._

Figure 258. Distribution of tone1.

***Figure 259.*** _Map of *tone1*._

Figure 259. Map of tone1.

***Figure 260.*** _Relationship between *tone1*, *ASPM*-D and *MCPH1*-D._

Figure 260. Relationship between tone1, ASPM-D and MCPH1-D.

Regressions

glmer
All data

trying to fit a random effects structure with language family as the random effects results in convergence problems (boundary (singular) fit: see ?isSingular) and the random effects seems to not matter at all (Can't compute random effect variances. Some variance components equal zero. Your model may suffer from singulariy. Solution: Respecify random structure!), so that I reverted to a “flat” model without random effects (using glm() instead of glmer()). As expected, the anova() comparisons produce the same p-values for this glm “flat” approach as for the glmer with family as random effects, but without the convergence issues…

  • null model: R2 = 0.0%
  • ASPM:
    • by itself: R2 = 3.6%, β = -0.38 ± 0.36, pASPM/null = 0.29
    • quadratic: R2 = 9.2%, βASPM2 = 0.74 ± 0.94, pASPM2/ASPM = 0.18
  • MCPH1:
    • by itself: R2 = 2.9%, β = -0.36 ± 0.38, pMCPH1/null = 0.34
    • quadratic: R2 = 7.7%, βMCPH12 = 0.15 ± 0.57, pMCPH12/MCPH1 = 0.23
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 3.9%, βASPM = -0.28 ± 0.53, pASPM/MCPH1 = 0.6, βMCPH1 = -0.14 ± 0.55, pMCPH1/ASPM = 0.8, pASPM+MCPH1/null = 0.56,
    • interaction: R2 = 12.1%, pASPM:MCPH1/ASPM+MCPH1 = 0.085
Randomization

1000 independent replications.

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 64% 6% 7% 31% 8% 38%
unrestricted none alleles-together 61% 7% 8% 28% 7% 40%
unrestricted none alleles-independent 61% 8% 8% 22% 6% 32%
families none tone 55% 5% 3% 10% 5% 60%
families none alleles-together 51% 5% 4% 10% 4% 59%
families none alleles-independent 55% 5% 5% 19% 6% 51%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 261.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 33.7% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = 23.4, mean = 24.18, *p* = 1), and 34.1% when controlling for *MCPH1* (*t*(999) = 5.6, mean = 58.21, *p* = 1). For *MCPH1*-D (right): 34.3% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = 10.0, mean = 11.26, *p* = 1), and 43.6% when controlling for *ASPM* (*t*(999) = -2.8, mean = -8.39, *p* = 0.003)._

Figure 261. Results for 1000 restricted samplings. For ASPM-D (left): 33.7% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = 23.4, mean = 24.18, p = 1), and 34.1% when controlling for MCPH1 (t(999) = 5.6, mean = 58.21, p = 1). For MCPH1-D (right): 34.3% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = 10.0, mean = 11.26, p = 1), and 43.6% when controlling for ASPM (t(999) = -2.8, mean = -8.39, p = 0.003).

brms
  • ASPM only:
    • β = -0.64, 89%HDI = [-1.50, 0.35]
    • posterior probability p(β<0) = 0.88 (evidence ratio = 7.1), p(β=0) = 0.78 (evidence ratio = 3.6)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 17.5%; pROPE = 0.156
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(57%:43%) K=]: moderate evidence for null against ASPM (BF=3.4), LOO=0.43 [SE=1.11], WAIC=0.27 [SE=1.10], KFOLD=0.58 [SE=1.46]
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(57%:43%) K=]: moderate evidence for null against ASPM (BF=3.4), LOO=0.43 [SE=1.11], WAIC=0.27 [SE=1.10], KFOLD=0.58 [SE=1.46]
  • MCPH1 only:
    • β = -0.49, 89%HDI = [-1.30, 0.34]
    • posterior probability p(β<0) = 0.83 (evidence ratio = 5.1), p(β=0) = 0.82 (evidence ratio = 4.5)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 21.7%; pROPE = 0.194
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(68%:32%) K>]: moderate evidence for null against MCPH1 (BF=4.01), LOO=0.81 [SE=0.95], WAIC=0.75 [SE=0.95], KFOLD=1.98 [SE=1.30]
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(68%:32%) K>]: moderate evidence for null against MCPH1 (BF=4.01), LOO=0.81 [SE=0.95], WAIC=0.75 [SE=0.95], KFOLD=1.98 [SE=1.30]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L> W>(78%:22%) K>]: strong evidence for null against both (BF=14.4), LOO=1.65 [SE=1.24], WAIC=1.25 [SE=1.23], KFOLD=2.22 [SE=1.46]
    • interaction:
      • posterior probability p(=0) = 0.55 (evidence ratio = 1.2)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 2%; pROPE = 0.049
      • comparison ‘no interaction’ vs ‘with interaction’: [B= L= W=(37%:63%) K=]: anecdotal evidence for no interaction against with interaction (BF=1.01), LOO=-0.18 [SE=1.85], WAIC=-0.51 [SE=1.70], KFOLD=-0.79 [SE=2.41]
    • ASPM (partial):
      • β = -0.62, 89%HDI = [-1.95, 0.72]
      • posterior probability p(β<0) = 0.77 (evidence ratio = 3.3), p(β=0) = 0.78 (evidence ratio = 3.6)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 17.7%; pROPE = 0.158
    • MCPH1 (partial):
      • β = -0.11, 89%HDI = [-1.39, 1.03]
      • posterior probability p(β<0) = 0.56 (evidence ratio = 1.3), p(β=0) = 0.81 (evidence ratio = 4.3)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 21%; pROPE = 0.187
***Figure 262.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 262.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 262. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 263.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 263.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 263. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 264.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 264.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 264. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 265.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 265.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 265. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

tone2

The resulting dataset has 37 observations, distributed among 31 unique Glottolg codes in 8 families (ranging from a minimum of 1 language per family to a maximum of 18, with a mean 4.6 and median 2 languages per family) and 1 macroareas.

There are 25:22:31 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 28 0 0 0 28
Yes 9 0 0 0 9
Sum 37 0 0 0 37
***Figure 266.*** _Distribution of *tone2*._

Figure 266. Distribution of tone2.

***Figure 267.*** _Map of *tone2*._

Figure 267. Map of tone2.

***Figure 268.*** _Relationship between *tone2*, *ASPM*-D and *MCPH1*-D._

Figure 268. Relationship between tone2, ASPM-D and MCPH1-D.

Regressions

glmer
All data
  • null model: R2 = 0.0%, ICC = 3.1%
  • ASPM:
    • by itself: R2 = 1.6%, β = -0.23 ± 0.47, pASPM/null = 0.6
    • quadratic: R2 = 5.8%, βASPM2 = 0.30 ± 0.94, pASPM2/ASPM = 0.5
  • MCPH1:
    • by itself: R2 = 0.1%, β = -0.06 ± 0.43, pMCPH1/null = 0.89
    • quadratic: R2 = 5.3%, βMCPH12 = 0.19 ± 0.56, pMCPH12/MCPH1 = 0.39
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 1.9%, βASPM = -0.31 ± 0.56, pASPM/MCPH1 = 0.58, βMCPH1 = 0.14 ± 0.57, pMCPH1/ASPM = 0.81, pASPM+MCPH1/null = 0.85,
    • interaction: R2 = 1.9%, pASPM:MCPH1/ASPM+MCPH1 = 0.98
Randomization
Regressions with randomizations for tone2.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 86% 7% 8% 34% 5% 61%
unrestricted none alleles-together 88% 9% 9% 40% 6% 60%
unrestricted none alleles-independent 87% 8% 7% 32% 7% 60%
families none tone 90% 7% 10% 55% 6% 39%
families none alleles-together 92% 7% 10% 54% 5% 43%
families none alleles-independent 87% 9% 11% 43% 6% 50%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 269.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 29.6% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = 7.8, mean = 1.59, *p* = 1) and 45.1% when controlling for *MCPH1* (*t*(999) = 9.3, mean = 2.47, *p* = 1). For *MCPH1*-D (right): 27% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = 9.5, mean = 11.06, *p* = 1) and 32.6% when controlling for *ASPM* (*t*(999) = 8.5, mean = 2.40, *p* = 1)._

Figure 269. Results for 1000 restricted samplings. For ASPM-D (left): 29.6% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = 7.8, mean = 1.59, p = 1) and 45.1% when controlling for MCPH1 (t(999) = 9.3, mean = 2.47, p = 1). For MCPH1-D (right): 27% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = 9.5, mean = 11.06, p = 1) and 32.6% when controlling for ASPM (t(999) = 8.5, mean = 2.40, p = 1).

brms
  • ASPM only:
    • β = -0.37, 89%HDI = [-1.88, 0.99]
    • posterior probability p(β<0) = 0.68 (evidence ratio = 2.1), p(β=0) = 0.79 (evidence ratio = 3.7)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 18.4%; pROPE = 0.164
    • comparison ‘null’ vs ‘ASPM’: [B> L> W=(61%:39%) K>>]: moderate evidence for null against ASPM (BF=3.68), LOO=0.85 [SE=0.79], WAIC=0.45 [SE=0.59], KFOLD=2.38 [SE=1.05]
    • comparison ‘null’ vs ‘ASPM’: [B> L> W=(61%:39%) K>>]: moderate evidence for null against ASPM (BF=3.68), LOO=0.85 [SE=0.79], WAIC=0.45 [SE=0.59], KFOLD=2.38 [SE=1.05]
  • MCPH1 only:
    • β = -0.3, 89%HDI = [-1.61, 0.97]
    • posterior probability p(β<0) = 0.65 (evidence ratio = 1.8), p(β=0) = 0.81 (evidence ratio = 4.4)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 21%; pROPE = 0.187
    • comparison ‘null’ vs ‘MCPH1’: [B> L>> W=(57%:43%) K=]: moderate evidence for null against MCPH1 (BF=4.69), LOO=1.13 [SE=0.45], WAIC=0.29 [SE=0.38], KFOLD=-0.04 [SE=0.93]
    • comparison ‘null’ vs ‘MCPH1’: [B> L>> W=(57%:43%) K=]: moderate evidence for null against MCPH1 (BF=4.69), LOO=1.13 [SE=0.45], WAIC=0.29 [SE=0.38], KFOLD=-0.04 [SE=0.93]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L> W=(58%:42%) K>>]: strong evidence for null against both (BF=14), LOO=1.57 [SE=0.80], WAIC=0.34 [SE=0.61], KFOLD=7.10 [SE=2.10]
    • interaction:
      • posterior probability p(=0) = 0.79 (evidence ratio = 3.7)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 18.1%; pROPE = 0.161
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L= W=(43%:57%) K<<]: moderate evidence for no interaction against with interaction (BF=3.54), LOO=0.27 [SE=0.81], WAIC=-0.28 [SE=0.34], KFOLD=-4.42 [SE=2.17]
    • ASPM (partial):
      • β = -0.2, 89%HDI = [-2.07, 1.53]
      • posterior probability p(β<0) = 0.58 (evidence ratio = 1.4), p(β=0) = 0.76 (evidence ratio = 3.1)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 15.5%; pROPE = 0.138
    • MCPH1 (partial):
      • β = -0.24, 89%HDI = [-1.83, 1.37]
      • posterior probability p(β<0) = 0.57 (evidence ratio = 1.3), p(β=0) = 0.78 (evidence ratio = 3.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 17.9%; pROPE = 0.159
***Figure 270.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 270.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 270. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 271.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 271.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 271. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 272.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 272.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 272. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 273.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 273.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 273. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Tone counts

The resulting dataset has 38 observations, distributed among 32 unique Glottolg codes in 8 families (ranging from a minimum of 1 language per family to a maximum of 19, with a mean 4.8 and median 2 languages per family) and 1 macroareas.

There are 25:22:32 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
0 9 0 0 0 9
1 10 0 0 0 10
2 16 0 0 0 16
3 2 0 0 0 2
5 1 0 0 0 1
Sum 38 0 0 0 38
***Figure 274.*** _Distribution of tone *counts*._

Figure 274. Distribution of tone counts.

***Figure 275.*** _Distribution of tone *counts* across the world._

Figure 275. Distribution of tone counts across the world.

***Figure 276.*** _Relationship between tone *counts* (colors) and the two alleles (frequency) by macroarea._

Figure 276. Relationship between tone counts (colors) and the two alleles (frequency) by macroarea.

Regressions

glmer
All data

trying to fit a random effects structure with language family as the random effects results in convergence problems (boundary (singular) fit: see ?isSingular) and the random effects seems to not matter at all (Can't compute random effect variances. Some variance components equal zero. Your model may suffer from singulariy. Solution: Respecify random structure!), so that I reverted to a “flat” model without random effects (using glm() instead of glmer()). As expected, the anova() comparisons produce the same p-values for this glm “flat” approach as for the glmer with family as random effects, but without the convergence issues…

  • null model:
  • ASPM:
    • by itself: , β = -0.07 ± 0.15, pASPM/null = 0.64
    • quadratic: , βASPM2 = 0.02 ± 0.32, pASPM2/ASPM = 0.75
  • MCPH1:
    • by itself: , β = -0.06 ± 0.14, pMCPH1/null = 0.66
    • quadratic: , βMCPH12 = -0.03 ± 0.17, pMCPH12/MCPH1 = 0.7
  • both alleles (no macroarea):
    • ASPM + MCPH1: , βASPM = -0.05 ± 0.18, pASPM/MCPH1 = 0.79, βMCPH1 = -0.04 ± 0.17, pMCPH1/ASPM = 0.82, pASPM+MCPH1/null = 0.88,
    • interaction: , pASPM:MCPH1/ASPM+MCPH1 = 0.53
Randomization

We performed 1000 independent replications:

Regressions with randomizations for tone counts.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 87% 2% 3% 41% 3% 40%
unrestricted none alleles-together 87% 4% 4% 42% 2% 42%
unrestricted none alleles-independent 86% 3% 4% 36% 2% 39%
families none tone 96% 1% 0% 33% 2% 76%
families none alleles-together 80% 0% 0% 36% 2% 74%
families none alleles-independent 86% 1% 0% 52% 3% 74%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 277.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 39.3% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = 9.9, mean = 0.07, *p* = 1) and 29.7% when controlling for *MCPH1* (*t*(999) = 15.4, mean = 0.10, *p* = 1). For *MCPH1*-D (right): 47.5% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = 5.2, mean = 0.04, *p* = 1) and 56.2% when controlling for *ASPM* (*t*(999) = -3.1, mean = -0.02, *p* = 0.00086)._

Figure 277. Results for 1000 restricted samplings. For ASPM-D (left): 39.3% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = 9.9, mean = 0.07, p = 1) and 29.7% when controlling for MCPH1 (t(999) = 15.4, mean = 0.10, p = 1). For MCPH1-D (right): 47.5% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = 5.2, mean = 0.04, p = 1) and 56.2% when controlling for ASPM (t(999) = -3.1, mean = -0.02, p = 0.00086).

brms
  • ASPM only:
    • β = -0.1, 89%HDI = [-0.38, 0.17]
    • posterior probability p(β<0) = 0.7 (evidence ratio = 2.4), p(β=0) = 0.94 (evidence ratio = 17)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 44.6%; pROPE = 0.397
    • comparison ‘null’ vs ‘ASPM’: [B>> L> W>(71%:29%) K=]: strong evidence for null against ASPM (BF=16.5), LOO=1.00 [SE=0.58], WAIC=0.89 [SE=0.53], KFOLD=-0.93 [SE=1.69]
    • comparison ‘null’ vs ‘ASPM’: [B>> L> W>(71%:29%) K=]: strong evidence for null against ASPM (BF=16.5), LOO=1.00 [SE=0.58], WAIC=0.89 [SE=0.53], KFOLD=-0.93 [SE=1.69]
  • MCPH1 only:
    • β = -0.05, 89%HDI = [-0.31, 0.20]
    • posterior probability p(β<0) = 0.62 (evidence ratio = 1.6), p(β=0) = 0.95 (evidence ratio = 20)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 50.4%; pROPE = 0.448
    • comparison ‘null’ vs ‘MCPH1’: [B>> L>> W>>(73%:27%) K<]: strong evidence for null against MCPH1 (BF=19.3), LOO=0.97 [SE=0.35], WAIC=0.99 [SE=0.31], KFOLD=-1.71 [SE=1.51]
    • comparison ‘null’ vs ‘MCPH1’: [B>> L>> W>>(73%:27%) K<]: strong evidence for null against MCPH1 (BF=19.3), LOO=0.97 [SE=0.35], WAIC=0.99 [SE=0.31], KFOLD=-1.71 [SE=1.51]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L>> W>>(85%:15%) K>>]: extreme evidence for null against both (BF=280), LOO=1.89 [SE=0.63], WAIC=1.74 [SE=0.59], KFOLD=1.47 [SE=0.69]
    • interaction:
      • posterior probability p(=0) = 0.95 (evidence ratio = 20)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 49.6%; pROPE = 0.441
      • comparison ‘no interaction’ vs ‘with interaction’: [B>> L> W>(70%:30%) K=]: strong evidence for no interaction against with interaction (BF=17.6), LOO=1.04 [SE=0.85], WAIC=0.86 [SE=0.74], KFOLD=0.67 [SE=1.07]
    • ASPM (partial):
      • β = -0.1, 89%HDI = [-0.42, 0.25]
      • posterior probability p(β<0) = 0.68 (evidence ratio = 2.1), p(β=0) = 0.93 (evidence ratio = 14)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 38.3%; pROPE = 0.341
    • MCPH1 (partial):
      • β = 0, 89%HDI = [-0.31, 0.33]
      • posterior probability p(β<0) = 0.5 (evidence ratio = 0.99), p(β=0) = 0.94 (evidence ratio = 16)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 43.6%; pROPE = 0.388
***Figure 278.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 278.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 278. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 279.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 279.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 279. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 280.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 280.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 280. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

Only Eurasia

Here I use only the Eurasian data points.

tone1

There are 126 observations, distributed among 74 unique Glottolg codes in 19 families (ranging from a minimum of 1 language per family to a maximum of 48, with a mean 6.6 and median 3 languages per family) and 1 macroareas.

There are 118:89:74 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 0 100 0 0 100
Yes 0 26 0 0 26
Sum 0 126 0 0 126
***Figure 281.*** _Distribution of *tone1*._

Figure 281. Distribution of tone1.

***Figure 282.*** _Map of *tone1*._

Figure 282. Map of tone1.

***Figure 283.*** _Relationship between *tone1*, *ASPM*-D and *MCPH1*-D._

Figure 283. Relationship between tone1, ASPM-D and MCPH1-D.

Regressions

glmer
All data
  • null model: R2 = 0.0%, ICC = 99.0%
  • ASPM:
    • by itself: R2 = 0.0%, β = 0.10 ± 0.56, pASPM/null = 0.86
    • quadratic: R2 = 0.6%, βASPM2 = 0.37 ± 0.86, pASPM2/ASPM = 0.057
  • MCPH1:
    • by itself: R2 = 0.0%, β = -0.07 ± 0.41, pMCPH1/null = 0.87
    • quadratic: R2 = 0.6%, βMCPH12 = -0.15 ± 0.48, pMCPH12/MCPH1 = 0.06
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 0.0%, βASPM = 0.16 ± 0.60, pASPM/MCPH1 = 0.79, βMCPH1 = -0.12 ± 0.45, pMCPH1/ASPM = 0.8, pASPM+MCPH1/null = 0.95,
    • interaction: R2 = 0.0%, pASPM:MCPH1/ASPM+MCPH1 = 0.64
Randomization

1000 independent replications.

Regressions on 1000 permuted data. The first 3 columns show the permutation constraints (if any), how the macroarea is considered (if at all), and what is permuted. The next columns show the percent of the permutations that, in order, have a better AIC compared to the original fit, are significantly better than the null model (thus testing the effect of both alleles simultaneously), have a significant effect of ASPM-D, have a smaller effect (β) of ASPM-D than the original fit, and the same for MCPH1-D.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 4% 5% 74% 6% 28%
unrestricted none alleles-together 95% 4% 6% 60% 4% 34%
unrestricted none alleles-independent 96% 5% 6% 62% 4% 35%
families none tone 74% 4% 5% 66% 3% 30%
families none alleles-together 96% 5% 4% 66% 4% 31%
families none alleles-independent 97% 6% 5% 68% 6% 37%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 284.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 99.9% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -86.0, mean = -0.93, *p* = 0), and 99.9% when controlling for *MCPH1* (*t*(999) = -4.2, mean = -7.89, *p* = 1.4e-05). For *MCPH1*-D (right): 98.9% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -58.5, mean = -1.18, *p* = 0), and 98.5% when controlling for *ASPM* (*t*(999) = -3.5, mean = -11.46, *p* = 0.00025)._

Figure 284. Results for 1000 restricted samplings. For ASPM-D (left): 99.9% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -86.0, mean = -0.93, p = 0), and 99.9% when controlling for MCPH1 (t(999) = -4.2, mean = -7.89, p = 1.4e-05). For MCPH1-D (right): 98.9% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -58.5, mean = -1.18, p = 0), and 98.5% when controlling for ASPM (t(999) = -3.5, mean = -11.46, p = 0.00025).

brms
  • ASPM only:
    • β = -0.14, 89%HDI = [-1.48, 1.34]
    • posterior probability p(β<0) = 0.57 (evidence ratio = 1.3), p(β=0) = 0.8 (evidence ratio = 3.9)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 19.2%; pROPE = 0.171
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(54%:46%) K=]: moderate evidence for null against ASPM (BF=3.77), LOO=0.25 [SE=0.63], WAIC=0.14 [SE=0.32], KFOLD=2.38 [SE=3.34]
    • comparison ‘null’ vs ‘ASPM’: [B> L= W=(54%:46%) K=]: moderate evidence for null against ASPM (BF=3.77), LOO=0.25 [SE=0.63], WAIC=0.14 [SE=0.32], KFOLD=2.38 [SE=3.34]
  • MCPH1 only:
    • β = -0.04, 89%HDI = [-1.16, 1.19]
    • posterior probability p(β<0) = 0.55 (evidence ratio = 1.2), p(β=0) = 0.83 (evidence ratio = 4.8)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 24%; pROPE = 0.214
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(51%:49%) K=]: moderate evidence for null against MCPH1 (BF=4.7), LOO=0.22 [SE=0.55], WAIC=0.06 [SE=0.28], KFOLD=-1.06 [SE=2.93]
    • comparison ‘null’ vs ‘MCPH1’: [B> L= W=(51%:49%) K=]: moderate evidence for null against MCPH1 (BF=4.7), LOO=0.22 [SE=0.55], WAIC=0.06 [SE=0.28], KFOLD=-1.06 [SE=2.93]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L= W=(50%:50%) K=]: strong evidence for null against both (BF=18.5), LOO=0.90 [SE=0.93], WAIC=0.00 [SE=0.43], KFOLD=-1.63 [SE=1.82]
    • interaction:
      • posterior probability p(=0) = 0.8 (evidence ratio = 3.9)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 18.6%; pROPE = 0.166
      • comparison ‘no interaction’ vs ‘with interaction’: [B> L= W=(48%:52%) K>]: moderate evidence for no interaction against with interaction (BF=3.76), LOO=0.55 [SE=0.60], WAIC=-0.07 [SE=0.38], KFOLD=4.85 [SE=2.79]
    • ASPM (partial):
      • β = -0.11, 89%HDI = [-1.68, 1.37]
      • posterior probability p(β<0) = 0.54 (evidence ratio = 1.2), p(β=0) = 0.78 (evidence ratio = 3.6)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 18.3%; pROPE = 0.163
    • MCPH1 (partial):
      • β = -0.06, 89%HDI = [-1.28, 1.29]
      • posterior probability p(β<0) = 0.54 (evidence ratio = 1.2), p(β=0) = 0.82 (evidence ratio = 4.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 22.6%; pROPE = 0.202
***Figure 285.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 285.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 285. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 286.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 286.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 286. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 287.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 287.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 287. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 288.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 288.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 288. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

tone2

The resulting dataset has 123 observations, distributed among 71 unique Glottolg codes in 19 families (ranging from a minimum of 1 language per family to a maximum of 47, with a mean 6.5 and median 3 languages per family) and 1 macroareas.

There are 115:86:71 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
No 0 105 0 0 105
Yes 0 18 0 0 18
Sum 0 123 0 0 123
***Figure 289.*** _Distribution of *tone2*._

Figure 289. Distribution of tone2.

***Figure 290.*** _Map of *tone2*._

Figure 290. Map of tone2.

***Figure 291.*** _Relationship between *tone2*, *ASPM*-D and *MCPH1*-D._

Figure 291. Relationship between tone2, ASPM-D and MCPH1-D.

Regressions

glmer
All data
  • null model: R2 = 0.0%, ICC = 98.7%
  • ASPM:
    • by itself: R2 = 0.0%, β = 0.03 ± 1.46, pASPM/null = 1
    • quadratic: R2 = 81.7%, βASPM2 = -191.71 ± 77.88, pASPM2/ASPM = 4e-05
  • MCPH1:
    • by itself: R2 = 0.1%, β = -0.63 ± 1.12, pMCPH1/null = 0.6
    • quadratic: R2 = 0.4%, βMCPH12 = -0.42 ± 1.31, pMCPH12/MCPH1 = 0.25
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 0.2%, βASPM = -0.02 ± 1.39, pASPM/MCPH1 = 1, βMCPH1 = -0.63 ± 1.11, pMCPH1/ASPM = 0.6, pASPM+MCPH1/null = 0.87,
    • interaction: R2 = 0.3%, pASPM:MCPH1/ASPM+MCPH1 = 0.72
Randomization
Regressions with randomizations for tone2.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 5% 6% 44% 5% 0%
unrestricted none alleles-together 90% 12% 12% 48% 10% 27%
unrestricted none alleles-independent 88% 12% 12% 49% 10% 28%
families none tone 49% 9% 10% 62% 4% 19%
families none alleles-together 80% 8% 10% 60% 4% 16%
families none alleles-independent 84% 10% 12% 68% 6% 19%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 292.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 99.9% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -72.3, mean = -1.10, *p* = 0) and 99.8% when controlling for *MCPH1* (*t*(999) = -65.0, mean = -1.31, *p* = 0). For *MCPH1*-D (right): 75.3% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -20.5, mean = -0.38, *p* = 9.5e-79) and 76.2% when controlling for *ASPM* (*t*(999) = -21.1, mean = -0.64, *p* = 2.1e-82)._

Figure 292. Results for 1000 restricted samplings. For ASPM-D (left): 99.9% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -72.3, mean = -1.10, p = 0) and 99.8% when controlling for MCPH1 (t(999) = -65.0, mean = -1.31, p = 0). For MCPH1-D (right): 75.3% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -20.5, mean = -0.38, p = 9.5e-79) and 76.2% when controlling for ASPM (t(999) = -21.1, mean = -0.64, p = 2.1e-82).

brms
  • ASPM only:
    • β = -1.44, 89%HDI = [-3.63, 1.13]
    • posterior probability p(β<0) = 0.84 (evidence ratio = 5.4), p(β=0) = 0.58 (evidence ratio = 1.4)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 6.9%; pROPE = 0.062
    • comparison ‘null’ vs ‘ASPM’: [B= L= W=(47%:53%) K>]: anecdotal evidence for null against ASPM (BF=1.49), LOO=-0.11 [SE=0.84], WAIC=-0.13 [SE=0.66], KFOLD=2.88 [SE=2.04]
    • comparison ‘null’ vs ‘ASPM’: [B= L= W=(47%:53%) K>]: anecdotal evidence for null against ASPM (BF=1.49), LOO=-0.11 [SE=0.84], WAIC=-0.13 [SE=0.66], KFOLD=2.88 [SE=2.04]
  • MCPH1 only:
    • β = -0.42, 89%HDI = [-2.51, 1.61]
    • posterior probability p(β<0) = 0.64 (evidence ratio = 1.8), p(β=0) = 0.72 (evidence ratio = 2.5)
    • ROPE = [-0.18, 0.18], % HDI inside ROPE = 12.8%; pROPE = 0.114
    • comparison ‘null’ vs ‘MCPH1’: [B= L= W<(45%:55%) K=]: anecdotal evidence for null against MCPH1 (BF=2.44), LOO=0.09 [SE=0.28], WAIC=-0.21 [SE=0.19], KFOLD=0.33 [SE=0.47]
    • comparison ‘null’ vs ‘MCPH1’: [B= L= W<(45%:55%) K=]: anecdotal evidence for null against MCPH1 (BF=2.44), LOO=0.09 [SE=0.28], WAIC=-0.21 [SE=0.19], KFOLD=0.33 [SE=0.47]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B> L< W<(31%:69%) K>]: moderate evidence for null against both (BF=3.62), LOO=-0.77 [SE=0.75], WAIC=-0.78 [SE=0.67], KFOLD=5.80 [SE=3.74]
    • interaction:
      • posterior probability p(=0) = 0.71 (evidence ratio = 2.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 11.8%; pROPE = 0.105
      • comparison ‘no interaction’ vs ‘with interaction’: [B= L>> W<(47%:53%) K<]: anecdotal evidence for no interaction against with interaction (BF=2.31), LOO=0.47 [SE=0.24], WAIC=-0.12 [SE=0.09], KFOLD=-5.61 [SE=3.74]
    • ASPM (partial):
      • β = -1.44, 89%HDI = [-4.09, 1.20]
      • posterior probability p(β<0) = 0.82 (evidence ratio = 4.6), p(β=0) = 0.59 (evidence ratio = 1.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 6.8%; pROPE = 0.06
    • MCPH1 (partial):
      • β = -0.52, 89%HDI = [-2.53, 1.68]
      • posterior probability p(β<0) = 0.66 (evidence ratio = 2), p(β=0) = 0.72 (evidence ratio = 2.5)
      • ROPE = [-0.18, 0.18], % HDI inside ROPE = 12.3%; pROPE = 0.11
***Figure 293.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 293.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 293. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 294.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 294.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 294. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 295.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 295.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 295. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

***Figure 296.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 296.*** _Confusion matrices for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 296. Confusion matrices for ASPM-D (left) and MCPH1-D (right).

Tone counts

The resulting dataset has 126 observations, distributed among 73 unique Glottolg codes in 19 families (ranging from a minimum of 1 language per family to a maximum of 47, with a mean 6.6 and median 3 languages per family) and 1 macroareas.

There are 115:86:73 unique samples:(meta)populations:languages retained.

  Africa Eurasia America Papunesia Sum
0 0 98 0 0 98
1 0 6 0 0 6
2 0 3 0 0 3
3 0 5 0 0 5
4 0 8 0 0 8
5 0 4 0 0 4
6 0 2 0 0 2
Sum 0 126 0 0 126
***Figure 297.*** _Distribution of tone *counts*._

Figure 297. Distribution of tone counts.

***Figure 298.*** _Distribution of tone *counts* across the world._

Figure 298. Distribution of tone counts across the world.

***Figure 299.*** _Relationship between tone *counts* (colors) and the two alleles (frequency) by macroarea._

Figure 299. Relationship between tone counts (colors) and the two alleles (frequency) by macroarea.

Regressions

glmer
All data
  • null model: R2 = 0.0%, ICC = 100.0%
  • the Poisson model is not overdispersed: χ2(124) = 64.3, p = 1
  • ASPM:
    • by itself: R2 = 0.0%, β = 0.05 ± 0.27, pASPM/null = 0.84
    • quadratic: R2 = 27.2%, βASPM2 = -1.02 ± 0.60, pASPM2/ASPM = 0.013
  • MCPH1:
    • by itself: R2 = 0.4%, β = -0.20 ± 0.17, pMCPH1/null = 0.26
    • quadratic: R2 = 0.8%, βMCPH12 = -0.15 ± 0.18, pMCPH12/MCPH1 = 0.15
  • both alleles (no macroarea):
    • ASPM + MCPH1: R2 = 0.4%, βASPM = 0.00 ± 0.26, pASPM/MCPH1 = 0.99, βMCPH1 = -0.20 ± 0.17, pMCPH1/ASPM = 0.27, pASPM+MCPH1/null = 0.53,
    • interaction: R2 = 0.5%, pASPM:MCPH1/ASPM+MCPH1 = 0.64
Randomization

We performed 1000 independent replications:

Regressions with randomizations for tone counts.
Permute within Macroarea Permute AIC Signif. pASPM-D βASPM-D pMCPH1-D βMCPH1-D
unrestricted none tone 0% 37% 25% 47% 26% 16%
unrestricted none alleles-together 46% 3% 3% 50% 3% 4%
unrestricted none alleles-independent 48% 2% 3% 52% 3% 4%
families none tone 47% 5% 11% 74% 1% 10%
families none alleles-together 49% 5% 10% 74% 1% 9%
families none alleles-independent 47% 4% 8% 70% 1% 7%
Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for *macroarea* (vertical panels) in terms of the effect size *&beta;*; *ASPM*-D is on the left and *MCPH1*-D on the right. The vertical dotted black thin line is at 0.0.

Regressions on 1000 permuted data. Each plot shows the original result (vertical dashed black line) and the distribution of the permutations for the three possible things to be permuted (colored curves) for each combination of permutation constraints (horizontal panels) and control for macroarea (vertical panels) in terms of the effect size β; ASPM-D is on the left and MCPH1-D on the right. The vertical dotted black thin line is at 0.0.

Restricted sampling
***Figure 300.*** _Results for 1000 restricted samplings. For *ASPM*-D (left): 99.9% of &beta;s are negative when regressing tone on *ASPM* alone (one-sided *t*-test < 0: *t*(999) = -86.3, mean = -0.69, *p* = 0) and 99.9% when controlling for *MCPH1* (*t*(999) = -88.2, mean = -0.76, *p* = 0). For *MCPH1*-D (right): 62.9% of &beta;s are negative when regressing tone on *MCPH1* alone (one-sided *t*-test < 0: *t*(999) = -9.3, mean = -0.11, *p* = 4.3e-20) and 63.7% when controlling for *ASPM* (*t*(999) = -7.7, mean = -0.13, *p* = 1.7e-14)._

Figure 300. Results for 1000 restricted samplings. For ASPM-D (left): 99.9% of βs are negative when regressing tone on ASPM alone (one-sided t-test < 0: t(999) = -86.3, mean = -0.69, p = 0) and 99.9% when controlling for MCPH1 (t(999) = -88.2, mean = -0.76, p = 0). For MCPH1-D (right): 62.9% of βs are negative when regressing tone on MCPH1 alone (one-sided t-test < 0: t(999) = -9.3, mean = -0.11, p = 4.3e-20) and 63.7% when controlling for ASPM (t(999) = -7.7, mean = -0.13, p = 1.7e-14).

brms
  • ASPM only:
    • β = -0.19, 89%HDI = [-0.77, 0.37]
    • posterior probability p(β<0) = 0.7 (evidence ratio = 2.4), p(β=0) = 0.89 (evidence ratio = 8.2)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 20.9%; pROPE = 0.186
    • comparison ‘null’ vs ‘ASPM’: [B> L>> W>>(75%:25%) K=]: moderate evidence for null against ASPM (BF=9.85), LOO=1.67 [SE=0.55], WAIC=1.09 [SE=0.41], KFOLD=0.57 [SE=1.33]
    • comparison ‘null’ vs ‘ASPM’: [B> L>> W>>(75%:25%) K=]: moderate evidence for null against ASPM (BF=9.85), LOO=1.67 [SE=0.55], WAIC=1.09 [SE=0.41], KFOLD=0.57 [SE=1.33]
  • MCPH1 only:
    • β = -0.1, 89%HDI = [-0.44, 0.23]
    • posterior probability p(β<0) = 0.69 (evidence ratio = 2.2), p(β=0) = 0.93 (evidence ratio = 13)
    • ROPE = [-0.10, 0.10], % HDI inside ROPE = 37%; pROPE = 0.329
    • comparison ‘null’ vs ‘MCPH1’: [B>> L>> W>>(79%:21%) K=]: strong evidence for null against MCPH1 (BF=16.8), LOO=1.75 [SE=0.48], WAIC=1.30 [SE=0.38], KFOLD=-0.32 [SE=1.41]
    • comparison ‘null’ vs ‘MCPH1’: [B>> L>> W>>(79%:21%) K=]: strong evidence for null against MCPH1 (BF=16.8), LOO=1.75 [SE=0.48], WAIC=1.30 [SE=0.38], KFOLD=-0.32 [SE=1.41]
  • both alleles:
    • comparison ‘null’ vs ‘both’: [B>> L>> W>>(85%:15%) K=]: very strong evidence for null against both (BF=92.8), LOO=2.74 [SE=0.92], WAIC=1.75 [SE=0.66], KFOLD=-0.19 [SE=1.57]
    • interaction:
      • posterior probability p(=0) = 0.9 (evidence ratio = 9.3)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 24.8%; pROPE = 0.221
      • comparison ‘no interaction’ vs ‘with interaction’: [B>> L= W=(52%:48%) K>>]: strong evidence for no interaction against with interaction (BF=10.4), LOO=-0.14 [SE=0.62], WAIC=0.09 [SE=0.31], KFOLD=3.56 [SE=1.62]
    • ASPM (partial):
      • β = -0.21, 89%HDI = [-0.79, 0.36]
      • posterior probability p(β<0) = 0.72 (evidence ratio = 2.5), p(β=0) = 0.89 (evidence ratio = 8)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 21.6%; pROPE = 0.192
    • MCPH1 (partial):
      • β = -0.12, 89%HDI = [-0.49, 0.19]
      • posterior probability p(β<0) = 0.71 (evidence ratio = 2.5), p(β=0) = 0.93 (evidence ratio = 13)
      • ROPE = [-0.10, 0.10], % HDI inside ROPE = 34.4%; pROPE = 0.306
***Figure 301.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 301.*** _Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 301. Posterior distributions (with 50% probability mass highlighted) versus 0.0 (the vertical line) for ASPM-D (left) and MCPH1-D (right).

***Figure 302.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 302.*** _Conditional effects of *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 302. Conditional effects of ASPM-D (left) and MCPH1-D (right).

***Figure 303.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._***Figure 303.*** _Posterior predictive checks for *ASPM*-D (left) and *MCPH1*-D (right)._

Figure 303. Posterior predictive checks for ASPM-D (left) and MCPH1-D (right).

Only America

Too little data…

Only Papunesia

Too little data…

Appendix VII: Draw diagrams for paper

Generic mediation model with a single mediator

Generic mediation model with a two mediators or a path analysis

tone1: simultaneous mediation through both alleles

tone1: path analysis (numeric coding)

tone1: path analysis (restricted sampling)

tone2: simultaneous mediation through both alleles

tone2: path analysis (numeric coding)

tone2: path analysis (restricted sampling)

Tone counts: simultaneous mediation through both alleles

Tone counts: path analysis

Tone counts: path analysis (restricted sampling)

Session information

CPU: AMD Ryzen 7 3700X 8-Core Processor (16 threads)

RAM (memory): 67.5 GB

R version 4.0.5 (2021-03-31)

Platform: x86_64-pc-linux-gnu (64-bit)

locale: LC_CTYPE=en_US.UTF-8, LC_NUMERIC=C, LC_TIME=en_US.UTF-8, LC_COLLATE=en_US.UTF-8, LC_MONETARY=en_US.UTF-8, LC_MESSAGES=en_US.UTF-8, LC_PAPER=en_US.UTF-8, LC_NAME=C, LC_ADDRESS=C, LC_TELEPHONE=C, LC_MEASUREMENT=en_US.UTF-8 and LC_IDENTIFICATION=C

attached base packages: grid, stats, graphics, grDevices, utils, datasets, methods and base

other attached packages: benchmarkme(v.1.0.7), magick(v.2.7.2), pdftools(v.3.0.1), rsvg(v.2.1.2), DiagrammeRsvg(v.0.1), simr(v.1.0.5), phytools(v.0.7-70), ape(v.5.5), tidybayes(v.2.3.1), bayestestR(v.0.9.0), brms(v.2.15.0), Rcpp(v.1.0.6), dagitty(v.0.3-1), e1071(v.1.7-6), cowplot(v.1.1.1), maps(v.3.3.0), lavaanPlot(v.0.5.1), lavaan(v.0.6-8), randomForest(v.4.6-14), caret(v.6.0-86), lattice(v.0.20-44), partykit(v.1.2-13), libcoin(v.1.0-8), rsample(v.0.1.0), mediation(v.4.5.0), sandwich(v.3.0-0), mvtnorm(v.1.1-1), MASS(v.7.3-54), DiagrammeR(v.1.0.6.1), pbapply(v.1.4-3), sjPlot(v.2.8.7), ggnewscale(v.0.4.5), glmmTMB(v.1.0.2.1), data.table(v.1.14.0), reshape2(v.1.4.4), dplyr(v.1.0.6), lmerTest(v.3.1-3), lme4(v.1.1-26), Matrix(v.1.3-3), performance(v.0.7.1), png(v.0.1-7), jpeg(v.0.1-8.1), tiff(v.0.1-8), gridExtra(v.2.3), ggplot2(v.3.3.3), stringr(v.1.4.0), pander(v.0.6.3), knitr(v.1.33) and RhpcBLASctl(v.0.20-137)

loaded via a namespace (and not attached): estimability(v.1.3), ModelMetrics(v.1.2.2.2), coda(v.0.19-4), tidyr(v.1.1.3), clusterGeneration(v.1.3.7), dygraphs(v.1.1.1.6), rpart(v.4.1-15), inline(v.0.3.17), doParallel(v.1.0.16), generics(v.0.1.0), callr(v.3.7.0), combinat(v.0.0-8), proxy(v.0.4-25), future(v.1.21.0), RLRsim(v.3.1-6), lubridate(v.1.7.10), httpuv(v.1.6.1), StanHeaders(v.2.21.0-7), assertthat(v.0.2.1), gower(v.0.2.2), xfun(v.0.22), hms(v.1.0.0), ggdist(v.2.4.0), jquerylib(v.0.1.4), bayesplot(v.1.8.0), evaluate(v.0.14), promises(v.1.2.0.1), fansi(v.0.4.2), readxl(v.1.3.1), igraph(v.1.2.6), DBI(v.1.1.1), tmvnsim(v.1.0-2), htmlwidgets(v.1.5.3), stats4(v.4.0.5), benchmarkmeData(v.1.0.4), purrr(v.0.3.4), ellipsis(v.0.3.2), crosstalk(v.1.1.1), backports(v.1.2.1), binom(v.1.1-1), V8(v.3.4.2), pbivnorm(v.0.6.0), insight(v.0.14.0), markdown(v.1.1), RcppParallel(v.5.1.4), vctrs(v.0.3.8), sjlabelled(v.1.1.8), abind(v.1.4-5), withr(v.2.4.2), checkmate(v.2.0.0), emmeans(v.1.6.0), xts(v.0.12.1), prettyunits(v.1.1.1), mnormt(v.2.0.2), cluster(v.2.1.2), crayon(v.1.4.1), recipes(v.0.1.16), pkgconfig(v.2.0.3), nlme(v.3.1-152), nnet(v.7.3-16), rlang(v.0.4.11), globals(v.0.14.0), lifecycle(v.1.0.0), miniUI(v.0.1.1.1), colourpicker(v.1.1.0), modelr(v.0.1.8), cellranger(v.1.1.0), distributional(v.0.2.2), matrixStats(v.0.58.0), phangorn(v.2.7.0), loo(v.2.4.1), carData(v.3.0-4), boot(v.1.3-28), zoo(v.1.8-9), base64enc(v.0.1-3), gamm4(v.0.2-6), ggridges(v.0.5.3), processx(v.3.5.2), parameters(v.0.13.0), visNetwork(v.2.0.9), pROC(v.1.17.0.1), parallelly(v.1.25.0), qpdf(v.1.1), shinystan(v.2.5.0), ggeffects(v.1.1.0), scales(v.1.1.1), lpSolve(v.5.6.15), magrittr(v.2.0.1), plyr(v.1.8.6), threejs(v.0.3.3), compiler(v.4.0.5), rstantools(v.2.1.1), RColorBrewer(v.1.1-2), plotrix(v.3.8-1), cli(v.2.5.0), listenv(v.0.8.0), ps(v.1.6.0), TMB(v.1.7.20), Brobdingnag(v.1.2-6), htmlTable(v.2.1.0), Formula(v.1.2-4), mgcv(v.1.8-35), tidyselect(v.1.1.1), stringi(v.1.6.1), forcats(v.0.5.1), projpred(v.2.0.2), yaml(v.2.2.1), askpass(v.1.1), svUnit(v.1.0.6), latticeExtra(v.0.6-29), bridgesampling(v.1.1-2), sass(v.0.4.0), fastmatch(v.1.1-0), tools(v.4.0.5), rio(v.0.5.26), parallel(v.4.0.5), rstudioapi(v.0.13), foreach(v.1.5.1), foreign(v.0.8-81), inum(v.1.0-4), prodlim(v.2019.11.13), scatterplot3d(v.0.3-41), farver(v.2.1.0), digest(v.0.6.27), shiny(v.1.6.0), lava(v.1.6.9), quadprog(v.1.5-8), car(v.3.0-10), broom(v.0.7.6), later(v.1.2.0), httr(v.1.4.2), rsconnect(v.0.8.17), effectsize(v.0.4.4-1), sjstats(v.0.18.1), colorspace(v.2.0-1), splines(v.4.0.5), statmod(v.1.4.36), expm(v.0.999-6), shinythemes(v.1.2.0), xtable(v.1.8-4), jsonlite(v.1.7.2), nloptr(v.1.2.2.2), timeDate(v.3043.102), rstan(v.2.21.2), ipred(v.0.9-11), R6(v.2.5.0), Hmisc(v.4.5-0), pillar(v.1.6.0), htmltools(v.0.5.1.1), mime(v.0.10), glue(v.1.4.2), fastmap(v.1.1.0), minqa(v.1.2.4), DT(v.0.18), class(v.7.3-19), codetools(v.0.2-18), pkgbuild(v.1.2.0), furrr(v.0.2.2), utf8(v.1.2.1), bslib(v.0.2.5), tibble(v.3.1.1), pbkrtest(v.0.5.1), numDeriv(v.2016.8-1.1), arrayhelpers(v.1.1-0), curl(v.4.3.1), gtools(v.3.8.2), zip(v.2.1.1), openxlsx(v.4.2.3), shinyjs(v.2.0.0), survival(v.3.2-11), rmarkdown(v.2.8), munsell(v.0.5.0), iterators(v.1.0.13), haven(v.2.4.1), sjmisc(v.2.8.7) and gtable(v.0.3.0)

References

Dediu, D., & Ladd, D. R. (2007). Linguistic tone is related to the population frequency of the adaptive haplogroups of two brain size genes, ASPM and Microcephalin. Proc Natl Acad Sci U S A, 104(26), 10944–10949. https://doi.org/10.1073/pnas.0610848104
Evans, P. D., Gilbert, S. L., Mekel-Bobrov, N., Vallender, E. J., Anderson, J. R., Vaez-Azizi, L. M., … Lahn, B. T. (2005). Microcephalin, a gene regulating brain size, continues to evolve adaptively in humans. Science, 309(5741), 1717–1720. https://doi.org/10.1126/science.1113722
McElreath, R. (2020). Statistical Rethinking: A Bayesian Course with Examples in R and Stan (2nd ed.). CRC Press LLC.
Mekel-Bobrov, N., Gilbert, S. L., Evans, P. D., Vallender, E. J., Anderson, J. R., Hudson, R. R., … Lahn, B. T. (2005). Ongoing adaptive evolution of ASPM, a brain size determinant in Homo sapiens. Science, 309(5741), 1720–1722. https://doi.org/10.1126/science.1116815
Wong, Patrick C. M., Chandrasekaran, B., & Zheng, J. (2012). The Derived Allele of ASPM Is Associated with Lexical Tone Perception. PLoS One, 7(4), e34243. https://doi.org/10.1371/journal.pone.0034243
Wong, Patrick C. M., Kang, X., Wong, K. H. Y., So, H.-C., Choy, K. W., & Geng, X. (2020). ASPM-lexical tone association in speakers of a tone language: Direct evidence for the genetic-biasing hypothesis of language evolution. Science Advances, 6(22), eaba5090. https://doi.org/10.1126/sciadv.aba5090

  1. For mixed-effects models, this is Nakagawa’s R2 estimate, where the marginal estimate considers only the fixed effects, while the conditional also considers the random effects as well. Here, we show only the marginal ICC, as we are interested in the fixed effects. See ?performance::r2 for more details.↩︎

  2. ICC represents the proportion of the variance explained by the grouping due to the random effects, and varies between 0% (the grouping contains no info) to 100% (basically all individual observations in a given group are identical); the adjusted ICC only considers the random effect, while the conditional ICC also considers the fixed effects as well; they are equal when there are no fixed effects (i.e., for the null models). Here, we show only the adjusted ICC, as we are interested in the random effects. See ?performance::icc for more details.↩︎

  3. Here I use model comparisons to estimate the p-value of adding (or removing) a predictor, v, by comparing the model without the predictor (m) with the model with the predictor (m_v), anova(m, m_v) and report the p-value denoted as pv/m to make clear what predictor is added to which model.↩︎

  4. The ROPE (region of practical equivalence) is a small interval around 0.0 (usually, [-0.1, 0.1] but can vary depending on the particular model). Can be used either to estimate the percent of the HDI that falls within this interval, or the proportion of the whole posterior distribution that does so. It can be used in a manner similar to that of frequentist p-values to judge if 0.0 can be ruled out as a probable value of the parameter of interest.↩︎

  5. This compares two brms models, m1 and m2, using Bayes Factors (BF), LOO, WAIC and KFOLD. For the latter three, I show the difference between m1 and m2 (in this order), and the SE of this difference; if the difference is negative (<0) then m1 is worse, while if it is positive (>0) m1 is better, but the “significance” of this difference can be interpreted only in the context of the SE. These results are summarized using the [B? L? W?(x%:y%) K?] notation, where the symbol * can be “=” when the models are pretty much equivalent, “<” if m1 is worse than m2 (and “<<” if this difference is really big), or “>” if m1 is better than m2 (and “>>” if this difference is really big); for WAIC (“W”) I also give the relative weights of the two models as (x%:y%).↩︎

  6. Please note that for path analyses/SEM models, we want the goodness-of-fit χ2 test to be non-significant, meaning that there is no reason to reject the hypothesis that the model fits the data. On the other hand, there is a plethora of goodness of fit indices (we show a few) where the idea is that the closer they are to 1.00 the better the model fits to the data.↩︎