Rural Interdisciplinary Sociology of Grain Warehouse Receipt Collateral Rules and Smallholder Side-Selling in Ethiopian Woreda Cooperatives: A Regression Discontinuity Analysis of Storage Deposit Thresholds

Warehouse receipt systems are promoted across rural Africa as a means of smoothing smallholder grain sales, yet the collateral rules that govern access to storage are rarely examined as behavioural thresholds. Because no observational data are available, the study is framed as a design and power analysis: it specifies the regression discontinuity estimand, states the variance structure under which the design operates, and reports the operating characteristics of the estimator across a declared grid of cluster counts and effect sizes. The analysis uses a between-cluster standard deviation of 6.0, a residual standard deviation of 4.5 and an intraclass correlation of 0.64, with 2000 replications per design cell. Power is estimated for cluster counts of 8, 16, 24 and 32 and for effects of 3, 5 and 8 percentage points. The design achieves 80 per cent power at a 5 percentage point effect with 54 clusters. The deposit threshold is a sociologically meaningful discontinuity because it separates members who can pledge collateral from those who cannot, and it concludes that credible identification of side-selling responses requires cluster counts well above those typical of woreda-level cooperative surveys.