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...

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...

This paper takes a step towards formalizing the theoretical interconnections among four post-Industrial Revolution phenomena - the industrialization and growth take-off of rich northern' nations, massive global income divergence, and rapid trade expansion. Specifically, we present a...

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 develop a model of growth driven by successive improvements in 'General Purpose Technologies' (GPT's), such as the steam engine, electricity, or micro-electronics. Each new generation of GPT's prompts investments in complementary inputs, and impacts the economy after enough such compatible...