"We model unemployment allowing workers to differ by comparative advantage in market work. Workers with comparative advantage are identified by who works more hours when employed. This enables us to test the model by grouping workers based on their long-term wages and hours from panel data. The...

"Whether technological progress raises or lowers aggregate employment in the short run has been the subject of much debate in recent years. Using a simple model of industry employment, we show that cross-industry differences of inventory holding costs, demand elasticities, and price rigidities...

We introduce worker differences in labor supply, reflecting differences in skills and assets, into a model of separations, matching, and unemployment over the business cycle. Separating from employment when unemployment duration is long is particularly costly for workers with high labor supply....