A striking pattern in transaction-level data is the concentration of international shipments in the hands of a few large firms. One common feature of dominating high-performance firms is that they produce multiple products and ship them to many destinations. Motivated by the emergence of highly...

What insights can be gained from bringing the theory of the firm to the global economy? I discuss several new features of the world economy that can be explained by incorporating the theory of the firm into the theory of international trade. Among the new features I discuss are the move to...

In this paper, we merge the heterogenous firm trade model of Melitz (2003) with the Ricardian model of Dornbusch, Fisher and Samuelson (DFS 1977) to explain how the pattern of international specialization and trade is determined by the interaction of comparative advantage, economies of scale,...

Fragmentation of the global value chain makes it difficult to assess the effects of trade liberalization on the global pattern of production. Gross bilateral trade ows no longer reveal a country's or a sector's value added contribution. Yet, it is value added that matters for employment and...

This paper introduces quality innovations with endogenous sunk costs in a heterogeneous firm model of international trade and derives implications for the gravity equation. The model predicts that the effect of fixed costs on exports and on the share of exporters is lower in industries with a...

Starting from the premise that productivity is heterogeneous across firms, Melitz (2003) explains why individual productivity is key in determining the capability of a firm to export. In this paper we build a model along Melitz's lines to show that also financial capacity, captured by the level...

On the eve of its 60th anniversary, the gravity model of trade is a "celebrity", due to its intuitive appeal, solid theoretical foundations, and remarkable empirical success. Yet, many economists still view gravity simply as an intuitive but naive reduced-form estimating equation and apply it...

Customs data reveal heterogeneity and granularity of relationships among buyers and sellers. A key insight is how more exports to a destination break down into more firms selling there and more buyers per exporter. We develop a quantitative general equilibrium model of firm-to-firm matching...

International trade is dominated by a small number of very large firms. Models of trade with heterogeneous firms have been developed to study the causes and consequences of this observation. The canonical model of trade with heterogeneous firms shows that trade leads to between-firm...

Using a novel common econometric specification, we examine the measurement of three important effects in international trade that historically have been addressed largely separately: the (partial) effects on trade of economic integration agreements, national borders, and bilateral distance....