Portfolio Choice in Research and Development
分析赢者通吃的专利机制如何影响竞争企业研发策略的风险性及重复研发的激励，比较纳什均衡与社会最优，发现风险偏好差异取决于发现日期的概率分布偏度。
We analyze the effects of a winner-take-all patent mechanism on the riskiness of the research strategies chosen by competingfirms, as well as on thefirms' incentives to duplicate research projects. Nash equilibrium choices are compared with the social optimum in a oneshot, simultaneous-move game in which competitors choose the riskiness or correlation of their research performances. We show that neither society nor firms have any preference for correlation per se, while the divergence between social and privately optimal levels of risk depends on skewness characteristics of the probability distribution over discovery dates and on levels of risk aversion.