Computes the half-width confidence interval for correlation coefficient using the nonparametric method proposed by Olivoto et al. (2018).
corr_ci(.data = NA, ..., r = NULL, n = NULL, by = NULL, verbose = TRUE)
.data | The data to be analyzed. It can be a data frame (possible with
grouped data passed from |
---|---|
... | Variables to compute the confidence interval. If not informed, all
the numeric variables from |
r | If |
n | The sample size if |
by | One variable (factor) to compute the function by. It is a shortcut
to |
verbose | If |
A tibble containing the values of the correlation, confidence interval, upper and lower limits for all combination of variables.
The half-width confidence interval is computed according to the following equation:
\[CI_w = 0.45304^r \times 2.25152 \times n^{-0.50089}\]
where \(n\) is the sample size and \(r\) is the correlation coefficient.
Olivoto, T., A.D.C. Lucio, V.Q. Souza, M. Nardino, M.I. Diel, B.G. Sari, D.. K. Krysczun, D. Meira, and C. Meier. 2018. Confidence interval width for Pearson's correlation coefficient: a Gaussian-independent estimator based on sample size and strength of association. Agron. J. 110:1-8. doi: 10.2134/agronj2016.04.0196
Tiago Olivoto tiagoolivoto@gmail.com
#> # A tibble: 105 x 6 #> Pair Corr n CI LL UL #> <chr> <dbl> <int> <dbl> <dbl> <dbl> #> 1 PH x EH 0.932 156 0.0858 0.846 1.02 #> 2 PH x EP 0.638 156 0.108 0.530 0.747 #> 3 PH x EL 0.380 156 0.133 0.247 0.513 #> 4 PH x ED 0.661 156 0.106 0.555 0.768 #> 5 PH x CL 0.325 156 0.139 0.186 0.464 #> 6 PH x CD 0.315 156 0.140 0.176 0.455 #> 7 PH x CW 0.505 156 0.120 0.384 0.625 #> 8 PH x KW 0.753 156 0.0988 0.655 0.852 #> 9 PH x NR 0.329 156 0.138 0.190 0.467 #> 10 PH x NKR 0.353 156 0.136 0.217 0.489 #> # ... with 95 more rows# By each level of the factor 'ENV' CI2 <- corr_ci(data_ge2, CD, TKW, NKE, by = ENV, verbose = FALSE) CI2#> # A tibble: 12 x 7 #> ENV Pair Corr n CI LL UL #> <fct> <chr> <dbl> <int> <dbl> <dbl> <dbl> #> 1 A1 CD x TKW 0.385 39 0.265 0.120 0.650 #> 2 A1 CD x NKE -0.0205 39 0.354 -0.374 0.333 #> 3 A1 TKW x NKE -0.589 39 0.225 -0.814 -0.363 #> 4 A2 CD x TKW 0.518 39 0.238 0.280 0.756 #> 5 A2 CD x NKE 0.710 39 0.205 0.505 0.915 #> 6 A2 TKW x NKE 0.0755 39 0.338 -0.263 0.414 #> 7 A3 CD x TKW 0.270 39 0.290 -0.0200 0.560 #> 8 A3 CD x NKE 0.271 39 0.290 -0.0194 0.561 #> 9 A3 TKW x NKE -0.389 39 0.264 -0.653 -0.125 #> 10 A4 CD x TKW 0.417 39 0.258 0.158 0.675 #> 11 A4 CD x NKE 0.477 39 0.246 0.230 0.723 #> 12 A4 TKW x NKE -0.259 39 0.293 -0.552 0.0334# }