This article uses household data from Benin to estimate the extent that markets in sub-Saharan Africa discount damaged maize. Stated preference methods indicate that a 10% increase in insect damage results in a 9% maize price discount. However, revealed preference methods indicate that this discount is only 3%. Discounts are larger immediately after harvest than they are in the lean period when maize is scarce. Our results help explain why many smallholder farmers sell maize at harvest rather than making the effort to preserve grain of good quality for later in the season when it may fetch a higher price
Kadjo, D., J. Ricker-Gilbert, and C. Alexander. "Estimating Price Discounts for Low-Quality Maize in sub-Saharan Africa: Evidence from Benin," World Development, 77(1), pgs 115-128.