We explore the usefulness of patent citations as a measure of the "importance" of a firm's patents, as indicated by the stock market valuation of the firm's intangible stock of knowledge. Using patents and citations for 1963--1995, we estimate Tobin's q equations on the ratios of R&D to assets...

The use of patents in economic research has been seriously hindered by the fact that patents vary enormously in their importance or value, and hence, simple patent counts cannot be informative about innovative output. The purpose of this article is to put forward patent counts weighted by...

We analyze the productivity of information technology in emergency response systems. ``Enhanced 911" (E911) is information technology that links caller identification to a location database and so speeds up emergency response. We assess the impact of E911 on health outcomes using Pennsylvania...

This article studies the determinants of commercialization strategy for start-up innovators. We examine whether the returns on innovation are earned through product market competition or through cooperation with established firms (through licensing, alliances, or acquisition). Our hypotheses are...