Measurement Error in Access to Markets

Studies in the microeconometric literature increasingly utilize distance to or time to reach markets or social services as determinants of economic issues. These studies typically use self-reported measures from survey data, often characterized by non-classical measurement error. This paper is the first validation study of access to markets data. New and unique data from Peru allow comparison of self-reported variables with scientifically calculated variables. We investigate the determinants of the deviation between imputed and self-reported data and show that it is non-classical and dependent on observable socio-economic variables. Our results suggest that studies using self-reported measures of access may be estimating biased effects.