A dynamic pricipal-agent problem as a feedback Stackelberg differentioal game

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 model is a Stackelberg di®erential game in which the players use feedback strategies. Whereas in general Stackelberg di®erential games with feedback strategy spaces the leader's optimization problem has non-standard features that make it extremely hard to solve, in the present case this problem can be rewritten as a standard optimal control problem. Two examples are used to illustrate our approach.