When economic activity is concentrated over space or over time, it is more efficient. Most production occurs in geographic hot spots, and most production occurs between 9 and 12 in the morning and 1 to 5 in the afternoon on weekdays. The thick-market efficiencies that encourage the concentration...

A Melitz-style model of monopolistic competition with heterogeneous firms is integrated into a simple New Economic Geography model to show that the standard assumption of identical firms is neither necessary nor innocuous. We show that re-locating to the big region is most attractive for the...

Using a general-equilibrium simulation model featuring nominal rigidities and monopolistic competition in product and labor markets, this paper estimates the macroeconomic benefits and international spillovers of an increase in competition. After calibrating the model to the euro area vs. the...

This paper analyzes the welfare implications of international spillovers related to productivity gains, changes in market size, or government spending. We introduce trade costs and endogenous varieties in a two-country general-equilibrium model with monopolistic competition, drawing a...

The basic competitive model with freely available technology is suited for static industries but misleading as applied to major innovative economies for which development of new technologies equals in magnitude around 10% of gross domestic investment. We distinguish free generic technology from...

When considering the incentive of a monopolist to adopt an innovation, the textbook model assumes that it can instantaneously and seamlessly introduce the new technology. In fact, firms often face major problems in integrating new technologies. In some cases, firms have to (temporarily) produce...

This paper examines how international flows of technological knowledge affect economic performance across industries and firms in different countries. Motivated by the large share of the world's technology investments made by firms that are active across borders, we focus on international trade...

Several Chinese cities have invested billions of dollars to construct new industrial parks. These place based investments solve the land assembly problem which allows many productive firms to co-locate close to each other. The resulting local economic growth creates new opportunities for real...

This paper identifies a new channel through which bankrupt firms impose negative externalities on non-bankrupt peers. The bankruptcy and liquidation of a retail chain weakens the economies of agglomeration in any given local area, reducing the attractiveness of retail centers for remaining...