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 inter- national trade and inspired the development of new theories emphasizing firm...

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...

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...

Despite the fact that importing and exporting are extremely rare firm activities, economists generally devote little attention to the role of firms when discussing international trade. This paper summarizes key differences between trading and non-trading firms, demonstrates how these differences...

This paper develops a general test of factor price equalization that is robust to unobserved regional productivity differences, unobserved region- industry factor quality differences and variation in production technology across industries. We test relative factor price equalization across...

Relative wages vary considerably across regions of the United Kingdom, with skill-abundantregions exhibiting lower skill premia than skill-scarce regions. This paper shows that thelocation of economic activity is correlated with the variation in relative wages. U.K. regionswith low skill premia...

This paper develops a general equilibrium model of multi-product firms and analyzes their behavior during trade liberalization. Firm productivity in a given product is modeled as a combination of firm-level "ability" and firmproduct- level "expertise", both of which are stochastic and unknown...

This paper examines the determinants of intra-firm trade in U.S. imports using detailed countryproduct data. We create a new measure of product contractibility based on the degree of intermediation in international trade for the product. We find important roles for the interaction of country and...

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

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...