How should firms be incentivized to adopt new technologies when the technical merits and spillovers of such technologies are uncertain? We show that, when information is dispersed but exogenous, efficiency can be induced with simple (constant) subsidies. When, instead, firms must also be...

In chapter I, we model monopolistic competition in the spirit of Blanchard and Kiyotaki (1987) and we study the implications of this market structure for the existence of dynamically inefficient equilibria. We show that, with free entry, the presence of some pure profit does not rule out dynamic...

These notes provide an intuitive introduction to dynamic programming. The first two Sections, which can be skipped, present the standard deterministic Ramsey model using the Lagrangian approach. Section 3 reformulates the Ramsey problem by means of a Bellman equation, while Section 4 shows how...