Title: The network structure of international trade
Description: "I build a simple dynamic model of the formation of an international social network of importers and exporters.  Firms can only export into markets in which they have a contact.  They acquire new contacts both at random, and via their network of existing contacts.  This model explains (i) the cross-sectional distribution of the number of foreign markets accessed by individual exporters, (ii) the cross-sectional geographic distribution of foreign contacts, and (iii) the dynamics of firm level exports.  I show that the firm level dynamics of trade can explain the observed cross section of firm level exports.  All theoretical predictions are supported by the data"--National Bureau of Economic Research web site.