We report a puzzling pair of facts concerning the organization of science. The concentration of research output is declining at the department level but increasing at the individual level. For example, in evolutionary biology, over the period 1980 to 2000, the fraction of citation-weighted...

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...

This study examines the effect of changes in the vintage distribution of cardiovascular system drugs on hospitalization and mortality due to cardiovascular disease using longitudinal country-level data. The vintage of a drug is the first year in which it was marketed anywhere in the world. We...

The empirical analysis in quot;International Ramp;D Spilloversquot; (Coe and Helpman, 1995) is first revisited by applying modern panel cointegration estimation techniques to an expanded data set that we have constructed for the purpose of this study. The new estimates confirm the key results...

The euro has arisen as a credible eventual competitor to the dollar as leading international currency, much as the dollar rose to challenge the pound 70 years ago. This paper uses econometrically-estimated determinants of the shares of major currencies in the reserve holdings of the world's...

Research which explores unchartered waters has a high potential for major impact but also carries a higher uncertainty of having impact. Such explorative research is often described as taking a novel approach. This study examines the complex relationship between pursuing a novel approach and...

In many growth models, economic growth arises from people creating ideas, and the long-run growth rate is the product of two terms: the effective number of researchers and their research productivity. We present a wide range of evidence from various industries, products, and firms showing that...