Lanjouw, Jean Olson; Schankerman, Mark - Suntory and Toyota International Centres for Economics … - 2002
We analyse the determinants of the decline in measured research productivity (the patent/R&D ratio)using panel data on manufacturing firms in the U.S. for the period 1980-93. We focus on three factors: the level of demand, the quality of patents, and technological exhaustion. We first develop an...