Import tariffs tend to be higher for final goods than for inputs, a phenomenon commonly referred to as tariff escalation. Yet neoclassical trade theory - and modern Ricardian trade models, in particular - predict that welfare-maximizing tariffs are uniform across sectors. We show that tariff...

We study changes in markups across 72 product markets from 2006 to 2018. A growing literature has documented a rise in markups over time using a production function approach; we instead employ the standard microeconomic method, which is to estimate demand and then invert firms' first-order...

We explore how firms respond to downstream product shocks. We find that affected firms increase R&D and make additional safety-related investments in their existing assets-in-place. These investments vary with firm capabilities and across shock severity. Competitors appear to vicariously learn...