We develop a microeconomic model of endogenous growth where clean and dirty technologies compete in production and innovation—in the sense that research can be directed to either clean or dirty technologies. If dirty technologies are more advanced to start with, the potential transition to...

Environmental economics has traditionally fallen in the domain of microeconomics, but recently approaches from macroeconomics have been applied to studying environmental policy. We focus on two macroeconomic tools and their application to environmental economics. First, real business cycle...

Research and development (Ramp;D) is a key determinant of long run productivity and welfare. A central issue is whether a decentralized economy undertakes too little or too much Ramp;D. We develop an endogenous growth model that incorporates parametrically four important distortions to Ramp;D:...

This paper explores the impact of trade on growth when firms are heterogeneous. We find that greater openness produces anti-and pro-growth effects. The Melitz-model selection effects raises the expected cost of introducing a new variety and this tends to slow the rate of new-variety introduction...

A model is developed in which two complementary forms of investment contribute to growth—technology and skill acquisition, and growth takes two forms—TFP and variety growth. The rate of TFP growth depends more heavily on the parameters governing skill accumulation, while variety growth...

In a second-best optimal growth setup with only factor taxes, it is in general optimal to fully replace capital by labor income taxation in the long run. We revisit this important issue by developing a human capital-based endogenous growth model with frictional labor search, allowing each firm...

An endogenous growth model is developed where each period firms invest in researching and developing new ideas. An idea increases a firm's productivity. By how much depends on how central the idea is to a firm's activity. Ideas can be bought and sold on a market for patents. A firm can sell an...

Census data from international sources covering 77% of the world's migrant population indicate that the skill composition of migrants in major destination countries, including the US, has been rising over the last 4 decades. Moreover, the population share of skilled migrants has been approaching...

We examine the concerns that new technologies will render labor redundant in a framework in which tasks previously performed by labor can be automated and new versions of existing tasks, in which labor has a comparative advantage, can be created. In a static version where capital is fixed and...