This paper reviews the new approach to international trade based on firm heterogeneity in differentiated product markets. This approach explains a variety of features exhibited in disaggregated trade data, including the higher productivity of exporters relative to non-exporters, within-industry...

Empirical studies of firms within industries consistently report substantial heterogeneity in measures of performance such as size and productivity. This paper explores the consequences of joint heterogeneity on the supply side (sellers) and the demand side (buyers) in international trade using...

The elasticity of substitution between goods from different countries---the Armington elasticity---is important for many questions in international economics, but its magnitude is subject to debate: the "macro" elasticity between home and import goods is often found to be smaller than the...

This paper proposes that quality differentiation is an important feature of the operations of multi-product firms. We develop a model in which manufacturers vary product quality across their product range by using inputs of different quality levels. Firms' core competency is in varieties of...

The unit values of internationally traded goods are heavily influenced by quality. We model this in an extended monopolistic competition framework where, in addition to choosing price, firms simultaneously choose quality. We allow countries to have non-homothetic demand for quality. The optimal...

We estimate a structural model of heterogeneous multiproduct firms to examine the sources of firm heterogeneity emphasized in the recent trade and macro literatures. Using Nielsen barcode data on prices and sales, we estimate elasticities of substitution within and between firms, and use the...

This paper builds a tractable partial equilibrium model in the spirit of Melitz (2003), which incorporates two dimensions of heterogeneity: firms specific productivity shocks and firm-market specific demand shocks. The structural parameters of interest are estimated using only cross-sectional...

This paper provides evidence on monopolistic competition models with endogenous technology by studying the effects of sectoral export variety on country productivity. The effects are estimated in a translog GDP function system based on data for 34 countries from 1982 to 1997. Country...

We develop a model of international trade with export quality requirements and two dimensions of firm heterogeneity. In addition to "productivity", firms are also heterogeneous in their "caliber" -- the ability to produce quality using fewer fixed inputs. Compared to single-attribute models of...

We develop an assignment theory to analyze the volume and composition of foreign direct investment (FDI). Firms conduct FDI by either engaging in greenfield investment or in cross-border acquisitions. Cross-border acquisitions involve firms trading heterogeneous corporate assets to exploit...