We discuss the selection of the socially optimal discount rate for public investment projects that entail costs and benefits in the very long run. More specifically, we examine in an expected utility framework how the uncertainty on the growth rate of the GNP per head affects this rate. Under...

We offer a rational expectations model of the dynamics of innovative industries. The fundamental value of innovations is uncertain and one must learn whether they are solid or fragile. Also, when the industry is new, it is difficult to monitor managers and make sure they exert the effort...