The division of labor between and within countries is driven by two fundamental forces, comparative advantage and increasing returns. We set up a simple Ricardian model with a Marshallian input sharing mechanism to study their interplay. The key insight that emerges is that the interaction...

The world is replete with spatial frictions. Shipping goods across cities entails trade frictions. Commuting within cities causes urban frictions. How important are these frictions in shaping the spatial economy? We develop and quantify a novel framework to address this question at three...

The core-periphery model by Krugman (1991) has two 'dramatic' implications: catastrophic agglomeration and locational hysteresis. We study this seminal model with CES instead of Cobb-Douglas upper tier preferences. This small generalization suffices to change these stark implications. For a wide...

Models of the new economic geography share a number of common conclusions, but also exhibit notable differences, in particular with respect to the shape of the location pattern and the efficiency of the market equilibrium. This reflects the fact that these models rely heavily on specific...

The robust empirical finding that exporting firms are systematically different from firms that merely serve domestic consumers has inspired the development of a new brand of trade theory, the theory of heterogeneous firms and trade. The establishment of a canonical model due to Melitz (2003) has...

We use unique plant-level data to study the link between the local availability of services and the decision of manufacturing firms to source materials from abroad. To guide our empirical analysis we develop a monopolistic-competition model of the materials sourcing decisions of heterogeneous...

Entrepreneurs who decide to enter an industry are faced with different levels of effective entry costs in different countries. These costs are heavily influenced by economic policy. What is not well understood is how international trade affects the government incentive to impact on entry costs,...

How are the welfare costs from monopoly distributed across U.S. households? We answer this question for the U.S. credit card industry, which is highly concentrated, charges interest rates that are 3.4 to 8.8 percentage points above perfectly competitive pricing, and has repeatedly lost antitrust...

This paper considers a labour market model of monopsonistic competition with taste-based discrimination against minority workers to study the effect of equal pay legislation on labour market inequality. When the taste for discrimination is small or competition is weak, the policy removes job...

We consider a labour market model of oligopsonistic wage competition and show that there is a holdup problem although workers do not have any bargaining power. When a firm invests more, it pays a higher wage in order to attract workers from competitors. Because workers participate in the returns...