This paper presents a model of cumulative innovation where firms are heterogeneous in their research ability. We study the optimal reward policy when the quality of the ideas and their subsequent development effort are private information. The optimal assignment of property rights must...

We develop a general equilibrium model of trade with endogenous human capital acquisition in job specific skills and imperfectly observable skills. We show that even if there are no ex-ante fundamental differences between countries there may be equilibria under international trade with...

This paper develops new econometric methods to estimate hospital quality and other models with discrete dependent variables and non-random selection. Mortality rates in patient discharge records are widely used to infer hospital quality. However, hospital admission is not random and some...