I use the aggregate behavior of three indicators of technology (employment of research scientists and engineers, patented inventions, and total factor productivity) to identify a plausible model of endogenous technological change. In the US (as well as in other developed countries) research...

Climate policies vary widely across countries, with some countries imposing stringent emissions policies and others doing very little. When climate policies vary across countries, energy-intensive industries have an incentive to relocate to places with few or no emissions restrictions, an effect...

We derive the optimal unilateral policy in a general equilibrium model of trade and climate change where one region of the world imposes a climate policy and the rest of the world does not. A climate policy in one region shifts activities—extraction, production, and consumption—in the other...

Customs data reveal heterogeneity and granularity of relationships among buyers and sellers. A key insight is how more exports to a destination break down into more firms selling there and more buyers per exporter. We develop a quantitative general equilibrium model of firm-to-firm matching...

We develop a parsimonious model of innovating firms rich enough to confront firm-level evidence. It captures the dynamic behavior of individual heterogeneous firms, describes the evolution of an industry with simultaneous entry and exit, and delivers a general equilibrium model of technological...