Farmer Training and Development 2008-2011

The evaluation design for this activity changed over the course of the evaluation due to problems faced during implementation. In its original conception, the independent evaluator, NORC, and MCA-Honduras planned to use a randomized experimental design involving randomized assignment of communities (aldeas) to treatment. Following a series of implementation problems, the final approach used was an econometric model that relied on a model-based approach to impact evaluation. As raised in the evaluator report, one key assumption is that the causal models are correct. This assumes that all important unobserved variables affecting selection, such as proven ex-ante ability to grow horticultural crops, are time invariant (i.e., are constant between the two survey rounds). Assumptions of the econometric model are:

1. The stable unit treatment value assumption (SUTVA, no macro effects assumption, partial equilibrium assumption) is made. This means that the effect (potential outcomes) on one individual are not affected by potential changes in the treatment exposure of other individuals. This implies, for example, that the program is not so large that the outcomes are correlated (e.g., that farmers would produce such a large number of horticultural crops that the market would collapse).
2. The causal models are correct. The key assumption here is that all important unobserved variables affecting selection are time invariant (i.e., are constant between the two survey rounds).
3. The program intervention represents a “forced change” in (experimental control of) the agricultural system in Honduras.
4. The half of the country treated before this evaluation began is similar to the half yet to be treated, with respect to relationships among the important causal variables represented in the causal model underlying the statistical analysis.