This chapter reviews the new approach to international trade based on firm heterogeneity in
differentiated product markets. This approach explains a variety of features exhibited in …

This chapter surveys recent developments in agglomeration theory within a unifying
framework. We highlight how locational fundamentals, agglomeration economies, the spatial …

We study the welfare costs of markups in a dynamic model with heterogeneous firms and
endogenous markups. We provide aggregation results summarizing the macro implications …

Trade is a cornerstone concept in economics worldwide. This updated second edition of the
essential graduate textbook in international trade brings readers to the forefront of …

How large are the intra-national trade costs that separate consumers in remote locations of
develo** countries from global markets? What do those barriers imply for the intra …

We study the procompetitive gains from international trade in a quantitative model with
endogenously variable markups. We find that trade can significantly reduce markup …

Little is known about optimal policy in the face of global supply chain disruptions. Should
governments promote resilience by subsidizing backup sources of input supply in multiple …

This article examines how product innovations led to inflation inequality in the United States
from 2004 to 2015. Using scanner data from the retail sector, I find that annual inflation for …

We study optimal spatial policies in a quantitative trade and geography framework with
spillovers and spatial sorting of heterogeneous workers. We characterize the spatial …

This paper analyzes a general equilibrium economy featuring input‐output connections,
imperfect competition, and external economies of scale owing to entry and exit. The …