We investigate the costs of transportation regulation using the example of agricultural markets in the United States. Using a large database of prices by state of agricultural commodities, we find that the coefficient of variation (as a measure of market integration between states) falls for...

In this paper we develop a new approach to measuring the gains from economic integration based on a generalization of the Ricardian model in which heterogeneous factors of production are allocated to multiple sectors in multiple local markets based on comparative advantage. We implement this...