The incorporation of increasing returns and imperfect competition into applied general-equilibrium (AGE) models, beginning with Harris (1984), led to much larger welfare effects from changes such as trade liberalization. But the imperfect competition side of these IO developments has often...

We measure the importance of increasing returns to scale and trade in medical services. Using Medicare claims data, we document that "imported" medical care -- services produced by a medical provider in a different region -- constitute about one-fifth of US healthcare consumption. Larger regions...