This paper develops and estimates a model of indivisibilities in shipping and economies of scale in consolidation. It uses highly detailed data on imports for which it is possible to observe the contents of individual containers. In the model, a firm is able to adapt to indivisibility...

In recent empirical literature on spatial agglomeration, many papers find evidence consistent with location-specific externalities of some sort. Our willingness to accept evidence of agglomeration economies depends on how well key estimation problems have been addressed. Three issues are...

We document a novel stylized fact: Using data for several countries, we show that export activity is disproportionately concentrated in larger cities – even more so than overall economic activity. We account for this fact by marrying elements of international trade and economic geography. We...

Urban agglomerations arise at least in part out of the interaction between economies of scale in production and market size effects. This paper develops a simple spatial framework to develop illustrative models of the determinants of urban location, of the number and size of cities, and of the...

We complete the study of comparative statics initiated in Caplin and Leahy [2010], which introduced a new mathematical apparatus for understanding NTU allocation markets, as such covering the housing market and other markets for large indivisible goods. We introduce homotopy methods to...

This paper analyzes a model that features frictions, an operative labor supply margin, and incomplete markets. We first provide analytic solutions to a benchmark model that includes indivisible labor and incomplete markets in the absence of trading frictions. We show that the steady state levels...