Yield effects of agricultural cooperative membership in developing countries: A meta-analysis

This study uses a meta-analysis to synthesize the effects of agricultural cooperative membership on the yield of crops and livestock. It collects 158 estimated yield effects from 42 studies, covering 19 developing countries. Our analysis finds evidence that there exists positive publication bias in the empirical literature, confirming that researchers and journals have a preference to publish articles that report positive and significant results. After correcting for publication bias, we find that cooperative membership has a small-sized and insignificant effect on the yield. The meta-regression analysis reveals that variation in the reported yield effects can be largely explained by the study attributes such as the sample type (full sample vs. subsample), membership ratio, econometric approaches (instrumental-variable based parametric approach, non-parametric approach or ordinary least square regression), effect size types (average treatment effects on the treated, average treatment effects, or coefficient), agro-product type (grain or others), and climate zones (tropical or non-tropical).

Automated summary

This study utilizes a meta-analysis to examine the impact of agricultural cooperative membership on crop and livestock yields. The research combines data from 42 studies conducted in 19 developing countries, resulting in 158 estimated yield effects. The findings indicate the presence of positive publication bias in the empirical literature, revealing a preference for publishing articles reporting positive and significant results. However, after adjusting for publication bias, it is concluded that cooperative membership has a minimal and insignificant effect on yield. The meta-regression analysis further identifies various study attributes that explain the variation in reported yield effects, including sample type, membership ratio, econometric approaches, effect size types, agro-product type, and climate zones.