In a series of papers, my colleagues and I have demonstrated that levels of per capita income, economic growth, and other economic and demographic dimensions are strongly correlated with geographical and ecological variables such as climate zone, disease ecology, and distance from the coast....

This paper addresses the complex relationship between geography and macroeconomic growth. We investigate the ways in which geography may matter directly for growth, controlling for economic policies and institutions, as well as the effects of geography on policy choices and institutions. We find...

We examine the evolution of market potential and its role in driving economic growth over the long twentieth century. Theoretically, we exploit a structural gravity model to derive a closed-form solution for a widely-used measure of market potential. We are thus able to express market potential...

We study the distribution of economic activity, as proxied by lights at night, across 250,000 grid cells of average area 560 square kilometers. We first document that nearly half of the variation can be explained by a parsimonious set of physical geography attributes. A full set of country...

Knowledge of how science is consumed in public domains is essential for a deeper understanding of the role of science in human society. While science is heavily supported by public funding, common depictions suggest that scientific research remains an isolated or 'ivory tower' activity, with...

This paper studies how recent investigations of foreign influence in research have affected the productivity of U.S. scientists in the field of life sciences. Using data from PubMed and Dimensions during 2010-2020, we compare scientists who collaborated with scientists in China during 2010-2014...

We construct a model of firm dynamics with heterogeneous productivity and distortions. The productivity distribution evolves endogenously as the result of the decisions of firms seeking to upgrade their productivity over time. Firms can adopt two strategies toward that end: imitation and...

We explore the determinants of research specialization across countries and its consequences for relative wages. Using a dynamic Ricardian model we examine the effects of faster international technology diffusion and lower trade barriers on the incentive to innovate. In the absence of any...

We explore the use of patent citations to measure the "basicness" and appropriability of inventions. We propose that the basicness of research underlying an invention can be characterized by the nature of the previous patents cited by an invention; that the basicness of research outcomes relates...

The recruitment of foreign scientists enhances US science through an expanded workforce but could also cause harm by displacing better connected domestic scientists, thereby reducing localized knowledge spillovers. We develop a model in which a sufficient condition for the absence of overall...