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...

Scientific freedom and openness are hallmarks of academia: relative to their counterparts in industry, academics maintain discretion over their research agenda and allow others to build on their discoveries. This paper examines the relationship between openness and freedom, building on recent...

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...

Is public R&D spending complementary and thus "additional" to private R&D spending, or does it substitute for and tend to "crowd out" private R&D? Conflicting answers are given to this question. We survey the body of available economectric evidence accumulated over the past 35 years. A framework...

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...

The information content of academic citations is subject to debate. This paper views premature death as a tragic quot;natural experiment,quot; outlining a methodology identifying the quot;citation death taxquot; -- the impact of death of productive economists on the patterns of their citations....

We develop a real options model of Ramp;D valuation, which takes into account the uncertainty in the quality of the research output, the time and cost to completion, and the market demand for the Ramp;D output. The model is then applied to study the problem of pharmaceutical under-investment in...

We examine how the spatial and social proximity of inventors affects knowledge flows, focusing especially on how the two forms of proximity interact. We develop a knowledge flow production function (KFPF) as a flexible tool for modeling access to knowledge and show that the optimal spatial...

Are scientific knowledge flows embodied in individuals, or "in the air"? To answer this question, we measure the effect of labor mobility in a sample of 9,483 elite academic life scientists on the citation trajectories associated with individual articles (resp. patents) published (resp. granted)...

This paper examines international and domestic collaborations using data from an original survey of corresponding authors and Web of Science data of articles that had at least one US coauthor in the fields of Particle and Field Physics, Nanoscience and Nanotechnology, and Biotechnology and...