Published October 21, 2026 | Version v1

Rural Cooperative Credit Access and Interdisciplinary Sociology Extension Uptake in Kenyan Arid Counties: A Regression Discontinuity Analysis of Savings-Group Eligibility Thresholds

  • 1. University of Nairobi

Description

Because no observational data are available, the study characterises the design's power to detect effects of 3, 5 and 8 percentage points across 8, 16, 24 and 32 clusters under a declared variance structure with an intraclass correlation of 0.64, between-cluster standard deviation of 6.0 and residual standard deviation of 4.5. Power was estimated across 2000 replications per design cell.54 clusters are required to detect a 5-percentage-point effect at 80% power, and that the minimum detectable effect declines steeply as cluster count rises from 8 to 32. The regression discontinuity design is feasible for evaluating savings-group thresholds only when the number of clusters exceeds the range typically available to single-programme evaluations in arid counties, and it derives the implications of this constraint for the design of interdisciplinary sociology extension evaluations.

Notes

Published in African Rural Development Studies (Interdisciplinary -, vol 27, issue 1, pp 57-70. DOI: 10.5281/zenodo.23541719. A Pan-African Research Journals (PARJ Africa) publication, https://parj.africa

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Journal article: https://parj.africa/ajis_ruraldev/article/view/36243 (URL)

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