Firm-to-firm connections in domestic and international production networks play a fundamental role in economic outcomes. Firm heterogeneity and the sparse nature of firm-to-firm connections implicitly discipline network structure. We find that a large group of well-established statistical...

Economic activity is highly unevenly distributed within cities, as reflected in the concentration of economic functions in specific locations, such as finance in the Square Mile in London. The extent to which this concentration reflects natural advantages versus agglomeration forces is central...

We generalize the closed-economy neoclassical growth model (CNGM) to allow for costly goods trade and capital flows with imperfect substitutability between countries. We develop a tractable, multi-country, quantitative model that matches key features of the observed data (e.g., gravity equations...

Research in international trade has changed dramatically over the last twenty years, as attention has shifted from countries and industries towards the firms actually engaged in international trade. The now-standard heterogeneous firm model posits measure zero firms that compete under...

This paper examines the response of industries and firms to changes in trade costs. Several new firm-level models of international trade with heterogeneous firms predict that industry productivity will rise as trade costs fall due to the reallocation of activity across plants within an industry....

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...

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 firm-product-level "expertise", both of which are stochastic and unknown...

This paper examines the role of changing factor endowments in the growth and decline of industries and regions. The implications of an endowment-based Heckscher-Ohlin trade model for plant entry and exit are tested on 20 years of data for the entire US manufacturing sector. The trade model...

This paper models the relationship between countries' distance from global economic activity, endogenous investments in education, and economic development. Firms in remote locations pay greater trade costs on both exports and intermediate imports, reducing the amount of value added left to...

Deardorff [Journal of International Economics 36 (1994) 167-175] offers an intuitively appealing test for factor price equality (FPE). He demonstrates that FPE is impossible if the set (i.e., lens) of points defined by regional factor abundance vectors does not lie within the set of points...