We develop a framework for studying trade in vertically and horizontally differentiated products. In our model, consumers with heterogeneous incomes and tastes purchase a homogeneous good as well as making a discrete choice of quality and variety of a differentiated product. The distribution of...

We develop a two-country model of endogenous innovation and imitation in order to study the interactions between these two processes. Firms in the North race to bring out the next generation of a set of technology-intensive products. Each product potentially can be improved a countably infinite...

We develop a model of repeated product improvements in a continuum of sectors. Each product follows a stochastic progression up a quality ladder. Progress is not uniform across sectors, so an equilibrium distribution of qualities evolves over time. But the rate of aggregate growth is constant....

This paper develops a new framework for examining the distributional consequences of international trade that incorporates firm and worker heterogeneity, search and matching frictions in the labor market, and screening of workers by firms. Larger firms pay higher wages and exporters pay higher...

We consider a model in which the level of taxes and seignorage are too low to finance government expenditures and debt service. Government debt will therefore grow without bound, implying the eventual need to change policy. Starting with utility maximization, we analyze the effect of the...

The management of the exchange rate is possible only if the government pursues a monetary-fiscal policy mix which is consistent with its exchange rate targets. In this paper with uncertainty concerning the length of individual life the real consequences of exchange rate management depend on the...

Recent research has emphasized firm heterogeneity as a source of comparative advantage. Combining this approach with labor market frictions and worker heterogeneity provides a framework for studying the impact of trade on unemployment and inequality. This paper reviews this approach and reports...

This paper develops a new framework for examining the distributional consequences of trade liberalization that is consistent with increasing inequality in every country, growth in residual wage inequality, rising unemployment, and reallocation within and between industries. While the opening of...