This document is designed to help researchers apply RCTs so they can gain a more accurate insight into the impacts of different extension strategies in different locations. It provides information on the benefits of an RCT approach in comparison to other impact evaluation models; provides a step-by-step implementation guide and a framework to avoid challenges; and demonstrates how an RCT approach was implemented within the context of the ‘Mind the Gap’ initiative.
Since the early 1990s, liberalization of the seed market in Tanzania has attracted several foreign companies that now market maize hybrids in the country. In this article, we analyze the impacts of proprietary hybrids on maize yields, production, and household living standards. We build on a recent survey of smallholder maize farmers in two zones of Tanzania. Hybrid adoption rates are 48% and 13% in the North and East, respectively. Average net yield gains of hybrids are 50-60%, and there are also significant profit effects.
In Sub-Sahara Africa, adoption rates of improved crop varieties remain relatively low, which is partly due to farmers’ limited access to information. In smallholder settings, information often spreads through informal networks. Better understanding of such networks could potentially help to spur innovation and farmers’ exposure to new technologies. This study uses survey data from Tanzania to analyze social networks and their role for the spread of information about improved varieties of maize and sorghum.