In this paper we explore the popular but controversial idea that developing countries benefit from abandoning policy neutrality vis-a-vis trade, FDI and resource allocation across industries. Are developing countries justified in imposing tariffs, subsidies, and tax breaks that imply distortions...

In this paper we explore the effect of trade policy on productivity and welfare in the now standard model of firm-level heterogeneity and product differentiation with monopolistic competition. To obtain sharp results, we restrict attention to an economy that takes as given the price of imports...

The Melitz model highlights the importance of the extensive margin (the number of firms exporting) for trade flows. Using the World Bank's Exporter Dynamics Database (EDD) featuring firm-level exports from 50 countries, we find that around 50% of variation in exports is along the extensive...

Is the variation in bilateral trade flows across countries primarily due to differences in the number of exporting firms (the extensive margin) or in the average size of an exporter (the intensive margin)? And how does this affect the estimation and quantitative implications of the Melitz (2003)...

We explore the implications of models with increasing returns, endogenous variety and firm-level heterogeneity for the quantification of the gains from trade. We first focus on the impact of trade liberalization on imported variety by analyzing the experience of Costa Rica from 1986 to 1992. We...

We develop a multi-sector gravity model with heterogeneous workers to quantify the aggregate and group-level welfare effects of trade. The model generalizes the specific-factors intuition to a setting with labor reallocation, leads to a parsimonious formula for the group-level welfare effects...

We study the gains from trade liberalization in models with monopolistic competition, firm-level heterogeneity, and variable markups. For a large class of demand functions used in the international macro and trade literature, we derive a parsimonious generalization of the welfare formula in...

About 8 cents out of every dollar spent in the United States is spent on imports. What if, because of a wall or some other extreme policy intervention, imports were to remain on the other side of the US border? How much would US consumers be willing to pay to prevent this hypothetical policy...

This paper presents a theory of trade agreements where "politics" play an central role. This stands in contrast with the standard theory, where even politically-motivated governments sign trade agreements only to deal with terms-of-trade externalities. We develop a model where governments may be...

Although economists have long been interested in the implications of Marshallian externalities (i.e., industry-level external economies of scale) for trading economies, the large number of equilibria that they typically imply has kept such externalities out of the recent quantitative trade...