We extend the literature on knowledge spillovers between firms by studying a dynamic duopoly model of R&D. Our analysis highlights the previously ignored welfare effects of spillovers through dynamic changes in industry concentration. In addition, we find that the impact of imperfect...

We study a dynamic duopoly model of R\&D to analyze the impact of imperfect appropriability on market structure and welfare. We pursue this analysis by extending the Markov-Perfect dynamic industry model proposed by Ericson and Pakes (EP) (1995), through the introduction of a non-proprietary...

When firms engaged in R&D are observably heterogeneous (in size) and policymakers are able to condition policy on the observed heterogeneity, what is the optimal policy? This paper starts with a static two-stage duopoly model of R&D competition with uncertainty and finds it welfare enhancing to...

We introduce a model of an infinitely-lived nonprofit organization facing donor crowd-out by government grants and credit constraints. The nonprofit chooses the optimal allocation of resources over time between providing service and fund-raising activities. We show that the response of...

When firms engaged in R&D are observably heterogenous (in size) and policymakers are able to condition policy on the observed heterogeneity, what is the optimal policy? This paper starts with a static two-stage duopoly model of R&D competition with uncertainty and finds it welfare enhancing to...