The impact of farmer field schools on knowledge and productivity: A study of potato farmers in the Peruvian Andes

This article uses data from a survey of potato farmers in Cajamarca, Peru, to examine the impact of a pilot FFS program on farmers' knowledge (as measured by a knowledge test score). Since there was no baseline survey documenting the knowledge of farmers prior to their participation in FFS, we rely on methods based on comparison groups. To deal with selection bias, we use propensity score matching (PSM) methods to build a statistical comparison group of farmers comparable to FFS graduates. This allows us to ensure that bias in the impact estimate due to selection on observables is minimized. Any remaining bias in the matching estimator can thus be attributed to unobserved characteristics. That said, given the low participation rate of farmers in this small pilot program, the sample of nonparticipants is very likely to include people who would participate if the program were more widely available. By assessing impact immediately after participation in FFS, we may be capturing short-term knowledge acquisition that may or may not last over time. However, by restricting the measure of knowledge to the results of a test score on IPM practices, our study does not do full justice to the stated purpose of the FFS program - to promote critical thinking and creativity. According to FFS scientists, critical thinking is most valuable in managing problems with pests and weather shocks, when farmers' knowledge on how to react to such problems is useful. Keeping in mind these limitations, our empirical results indicate that farmers who participated in the program have significantly more knowledge about IPM practices than those in the nonparticipant comparison group. © 2004 by The University of Chicago. All rights reserved.