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...

We estimate a structural model of heterogeneous multiproduct firms to examine the sources of firm heterogeneity emphasized in the recent trade and macro literatures. Using Nielsen barcode data on prices and sales, we estimate elasticities of substitution within and between firms, and use the...

This paper investigates the impact of outsourcing on sectoral reallocation in the U.S. over the period 1947-2007, and on the rise in services in particular. Roughly 40% of the growth of the service sector comes from professional and business services. This is an unusual industry as more than 90%...

We consider the dynamic relationship between product market entry regulation and equilibrium unemployment. The main theoretical contribution is combining a job matching model with monopolistic competition in the goods market and individual bargaining. We calibrate the model to US data and...

We study the productivity of US owned plants in the UK. Using a new dataset that identifies foreign and domestic MNEs, we find that UK MNEs are less productive than US affiliates, but as productive as non US foreign affiliates. We investigate the source of the US and MNE advantage. We find...