Why do investors keep buying underperforming mutual funds? To address this issue, we develop a one-period principal-agent model with a representative investor and a fund manager in an asymmetric information framework. This model shows that the investors perception of the fund plays the key role...

I study the properties of optimal long-term contracts in an environment in which the agent's type evolves stochastically over time. The model stylizes a buyer-seller relationship but the results apply quite naturally to many contractual situations including regulation and optimal...