Beyond average: are the yield and income impacts of adopting drought-tolerant maize varieties heterogeneous?
A.Y. Kamara, Amadu Yaya Kamara, Oyakhilomen Oyinbo, Julius Manda, Alpha Y. Kamara, Alpha Y. Kamara, Ezekiel O. Idowu, Joseph James Mbavai
Abstract
Assessing the benefits of adopting climate-resilient farming technologies without considering the heterogeneity among farmers, may not provide a sufficient evidence base for policy. Yet, most empirical studies do not go beyond documenting the average effects of climate-resilient technologies. Using farm household survey data from Nigeria, this paper examines whether and to what extent the yield and income impacts of adopting drought-tolerant maize varieties are heterogeneous. We used the stratification-multilevel, matching-smoothing and smoothing-differencing econometric methods to analyse the heterogeneous effects of the varieties on maize yield, crop income and household income. Our results show that the adoption of drought-tolerant maize varieties significantly increased maize yield, crop and household income. In addition, we find that the yield and income impacts of the adoption of drought-tolerant maize varieties are heterogeneous and depend on the farm households’ propensity to adopt the drought tolerant maize varieties. Specifically, we find that the estimated yield effects of the drought-tolerant maize varieties are larger for farmers with the highest propensity to adopt the varieties, which suggests a positive selection. Our results emphasize the need for proper targeting of interventions to incentivize the uptake of climate-resilient farming technologies in order to improve the outcomes of households in drought-prone areas.