We model the invention of new technologies and their diffusion across countries. Our model predicts that, eventually, all countries will grow at the same rate, with each country's productivity ranking determined by how rapidly it adopts inventions. The common growth rate depends on research...

Between 2007 and 2011 unemployment rose substantially in most European countries. During the same period a number of European countries experienced large declines in their external deficits. We use a general equilibrium, thirty-four country Ricardian model with potential wage inflexibility to...

We reconcile trade theory with plant-level export behavior, extending the Ricardian model to accommodate many countries, geographic barriers, and imperfect competition. Our model captures qualitatively basic facts about U.S. plants: (i) productivity dispersion, (ii) higher productivity among...

European countries do less research than Japan and the United States. We use a quantitative multi-country growth model to ask: (i) Why is this so? (ii) Would there be any benefit to expanding research in Europe? (iii) What various European research promotion policies do? We find that: (i)...

Measures of innovative activity show it to be concentrated in a small number of countries. Yet the benefits of innovation are experienced broadly. International trade is one conduit through which the benefits of innovation in one country can flow abroad. Technological diffusion is another. In...

We examine entry across 113 national markets in 16 different industries using a comprehensive data set of French manufacturing firms. The data are unique in indicating how much each firm exports to each destination. Looking across all manufacturers: (1) Firms differ substantially in export...

We examine entry across 113 national markets in 16 different industries using a comprehensive data set of French manufacturing firms. The data are unique in indicating how much each firm exports to each destination. Looking across all manufacturers: (1) Firms differ substantially in export...

A recent literature has introduced heterogeneous firms into models of international trade. This literature has adopted the convention of treating individual firms as points on a continuum. While the continuum offers many advantages this convenience comes at some cost: (1) Shocks to individual...

David Ricardo (1817) provided a mathematical example showing that countries could gain from trade by exploiting innate differences in their ability to make different goods. In the basic Ricardian example, two countries do better by specializing in different goods and exchanging them for each...