When firms make decisions about which product to manufacture at a more disaggregated level than observed in the data, measured firm productivity reflects both characteristics of the "firm" and attributes of the "products" that are non-randomly chosen by the firm. This paper develops a model of...

International trade models typically assume that producers in one country trade directly with final consumers in another. In the real world, of course, trade can involve long chains of potentially independent actors who move goods through wholesale and retail distribution networks. These...

Recent research in international trade emphasizes the importance of firms' extensive margins for understanding overall patterns of trade as well as how firms respond to specific events such as trade liberalization. In this paper, we use detailed U.S. trade statistics to provide a broad overview...

This Paper presents a model of international trade that features heterogeneous firms, relative endowment differences across countries, and consumer taste for variety. The Paper demonstrates that firm reactions to trade liberalization generate endogenous Ricardian productivity responses at the...

This paper examines how country, industry, and firm characteristics interact in general equilibrium to determine nations' responses to trade liberalization. When firms possess heterogeneous productivity, countries differ in relative factor abundance, and industries vary in factor intensity,...

This paper develops a model of endogenous product selection by firms. The theory is motivated by new evidence we present on the importance of product switching by U.S. manufacturers. Two-thirds of continuing firms change their product mix every five years, and product switches involve more than...

Firms’ decisions about which goods to produce are often made at a more disaggregate level than the data observed by empirical researchers. When products differ according to production technique or the way in which they enter demand, this data aggregation problem introduces a bias into standard...

This Paper develops a model of endogenous product selection by firms. The theory is motivated by new evidence we present on the importance of product switching by US manufacturers. Two-thirds of continuing firms change their product mix every five years, and product switches involve more than...

This paper reviews the empirical evidence on firm heterogeneity in international trade. A first wave of empirical findings from micro data on plants and firms proposed challenges for existing models of international trade and inspired the development of new theories emphasizing firm...