Welcome to Fantasyland: Comparing Approaches To Land Area Measurement In Household Surveys

In rural societies land is a major measure of wealth, a critical input in agricultural production, and a key variable for assessing agricultural performance and productivity. In the absence of cadastral information to refer to, measures of land plots have historically been taken with one of two approaches: traversing (very precise, but cumbersome), and farmers’ self-report (cheap, but marred by large, systematic measurement error). Recently, the advent of cheap handheld GPS devices has held promise of balancing cost and precision. There are, however, concerns about how GPS measures may perform on certain types of plots, or under given measurement conditions. Using purposely collected data from methodological validation studies conducted in Ethiopia, Nigeria, and Tanzania, this paper analyses the use of farmer self-reported area estimation against the primary objective measurement alternatives. Guided by analytical results, and with consideration for practical household survey implementation, the paper assesses the nature and magnitude of measurement error under different methods and proposes a set of recommendations for plot area measurement. Results largely point to the support of GPS measurement, with simultaneous collection of farmer self-reported areas.