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...

This paper sheds light on the questions, Why does knowledge spill over? and How does knowledge spill over? The answer to these questions we suggest lies in the incentives confronting scientists to appropriate the expected value of their knowledge considered in the context of their path-dependent...

Scientific research has played a critical role in the life of the university for a considerable period of time, both in Europe and in the US. While much remains the same in the relationship between science and the university, considerable change has occurred in recent years. Here we outline...

"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...