Costless Information and Costly Verification: A Case for Transparency

Abstract

A principal has to take a binary decision. She relies on information privately held by a completely biased agent. The principal cannot incentivize with transfers but can learn the agent's information at a cost. Additionally, the principal privately observes a signal correlated with the agent's type. Transparent mechanisms are optimal: unlike in standard results with correlation, the principal's payoff is the same as if her signal was public. They take a simple cut-off form: favorable signals ensure the agent's preferred action. Signals below this cut-off lead to the nonpreferred action unless the agent appeals. An appeal always triggers type verification.