We consider situations in which a principal tries to induce an agent to spend e®ort on accumulating a state variable that a®ects the well-being of both parties. The only incentive mechanism that the principal can use is a state-dependent transfer of her own utility to the agent. Formally, the...

We develop a model that incorporates salient features of growth in modern economies. We combine the expanding-variety growth model through horizontal innovations with a hierarchy of basic and applied research. The former extends the knowledge base, while the latter commercializes it. Two-way...

We consider dynamic optimization problems on one-dimensional state spaces. Un- der standard smoothness and convexity assumptions, the optimal solutions are characterized by an optimal policy function h mapping the state space into itself. There exists an extensive literature on the relation...

We study the Ramsey (1928) model under the assumption that households act strategically. We compute the Markov perfect equilib- rium for this model and compare it to the original, competitive equi- librium and to a strategic open-loop equilibrium proposed by Sorger (2002, 2005b). We show that,...

We modify the growth model with horizontal innovations from Romer (1990) and Jones (1995) by assuming that researchers can determine the quality of the products they invent. Because research effort increases with product quality, the researchers face a tradeoff between the quantity and the...