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...

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...