A validation of the ethnosurvey: The case of Mexico-U.S. migration

This article evaluates the validity of the ethnosurvey as a method of demographic data collection by analyzing the representativeness of the Mexican Migration Project (MMP) as a source of information on Mexico-U.S. migration. After briefly delineating the philosophy, structure, and organization of the MMP's ethnosurvey design, we describe MMP's public use dataset as well as Mexico's Encuesta Nacional de la Dinamica Demografica (ENADID) as a benchmark for its systematic evaluation. Although the MMP over-represents migrants in the western states and mid-sized communities, it yields a relatively accurate and valid profile of migrants to the United States. A comparison of multivariate models estimated using MMP and ENADID data suggests that whereas the former's sampling errors are small and yield biases that are substantively unimportant, the latter's potential for specification error and selection bias may seriously compromise results. Our comparison thus validates the ethnosurvey as an accurate and reliable method of data collection and the MMP as a good source of reasonably representative data on documented and undocumented migration to the United States.