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 shows that both relative wages and industry structure vary considerably across regions of the United Kingdom. In accordance with the neoclassical model of trade, regions abundant in a factor (i) exhibit lower relative prices of that factor than regions scarce in the factor, and (ii)...

Since the mid-1990s, researchers have used micro datasets to study countries' production and trade at the firm level and have found that exporting firms differ substantially from firms that solely serve the domestic market. Across a wide range of countries and industries, exporting firms have...

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...

We develop a methodology for identifying departures from relative factor price equality across regions that is valid under general assumptions about production, markets and factors. Application of this methodology to the United States reveals substantial and increasing deviations in relative...

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...