I study a dynamic principal agent model in which the effort cost of the agent is unknown to the principal. The principal is ambiguity averse, and designs a contract which is robust to the worst case effort cost process. Ambiguity divides the contract into two regions. After sufficiently high...

I study a continuous-time principal-agent model in which the principal is ambiguity averse about the agent's effort cost. The robust contract generates a seemingly excessive pay-performance sensitivity. The worst-case effort cost is high after good performance, but low after bad performance,...

We study venture capital finance with experimentation. An entrepreneur contracts with an investor and has private information about a project, which requires costly experimentation by both parties to succeed. In equilibrium, investors learn about the project from the arrival of exogenous...