Unproductive Migration Reconsidered: A Stochastic Frontier Production Function for Analyzing Internal Migration.

Many theoretical models of internal migration have been proposed, with different implications for the social optimality of migration. This paper measures the output gains and losses from migration by using stochastic frontier production functions to identify migrants' marginal revenue products in both origin and destination areas. After this output effect of migration has been calculated, adjustments are made for the negative externalities produced by migrants and for distorted domestic relative prices. At least in the Peruvian case, internal migration is shown to have increased gross domestic product. This result is quite robust and obtains both with and without the aforementioned adjustments. Copyright 1993 by Royal Economic Society.