We introduce firm and worker heterogeneity into a model of innovation-driven endogenous growth. Individuals who differ in ability sort into either a research sector or a manufacturing sector that produces differentiated goods. Each research project generates a new variety of the differentiated...

Using data assembled by the Global Environmental Monitoring System we examine the reduced-form relationship between various environmental indicators and the level of a country's per capita income. Our study covers four types of indicators: concentrations of urban air pollution; measures of the...

In this paper, we examine one channel through which the trade regime might affect growth in the long run. We model endogenous technological progress that results from profit maximizing investments by far-sighted entrepreneurs. Productivity in the research lab depends upon the "stock of knowledge...

We construct a model of growth based on endogenous technological change in a small, open economy. Entrepreneurs develop new intermediate products whenever the present value of potential profits exceeds the cost of R&D. Diversity of intermediates contributes to total factor productivity in the...

We construct a dynamic, two-country model of trade and growth in which endogenous technological progress results from the profit-maximizing behavior of entrepreneurs. We study the role that the external trading environment and that trade and industrial policies play in the determination of...