The main goal of this paper is to develop an empirical framework for evaluating the patient welfare benefits arising from pharmaceutical innovation. Extending previous studies of the welfare benefits from innovation (Trajtenberg, 1990; Hausman, 1996), this paper unpacks the separate choices made by...

This paper evaluates the sources of transitory market power in the market for personal computers (PCs) during the late 1980's. Our analysis is motivated by the coexistence of low entry barriers into the PC industry and high rates of innovative investment by a small number of PC manufacturers. We...

This paper studies the consequences of physician authority on pharmaceutical prescribing. Physicians engage in a costly process of particular conditions and characteristics. The relative efficiency of this matching process results from the diagnostic skill of the physician along with the...

This paper analyzes the terrorist threat following 9/11, and explores its implications for defense R&D. First, it reviews the composition of defense R&D since 9/11: big weapon systems still command 30% of defense R&D spending (legacy of the Cold War), vis-a-vis just about 13% for intelligence...

This paper asks the question: Can we see evidence of General Purpose Technologies in patent data? Using data on three million US patents granted between 1967 and 1999, and their citations received between 1975 and 2002, we construct a number of measures of GPTs, including generality, number of...