Impacts of plot size on maize yields and farm profits: Implications for sustainable land use and food security

Abstract

This paper examines the impact of plot size on maize yields and farm profits, using plot-level data collected from Chinese maize farmers in 2013 and 2015. Unlike previous studies that have used either a parametric or non-parametric model, this study estimates a semi-parametric model. This model simultaneously estimates the impact of plot size on maize yields and farm profits non-parametrically and the impact of other control variables on the two outcome variables parametrically, which provides more insights. The findings reveal that plot size affects maize yields and farm profits differently. There is a ‘pan-shaped’ relationship between plot size and maize yields. Specifically, we show that when increasing plot size from 0.1 to 1.5 mu and then to 65 mu, the maize yields decrease first and then become stable. When plot size is above 65 mu, maize yields increase as plot size increases. In comparison, our results indicate that as plot size increases, the farm profits of maize production monotonically increase. Our findings have important implications for sustainable land use and food security.