Collusion and Renegotiation in a Principal–Supervisor–Agent Relationship
研究了委托人-监督人-代理人三方关系中，委托人如何通过签订基于噪声信号的合同来防止合谋，并分析了在允许重新谈判时这种合同不再有效，合谋反而会发生。
We describe a principal–supervisor–agent relationship in which agent and supervisor may collude. To prevent collusion, the principal may contract on a noisy signal which is correlated with the occurrence of collusion. When the signal is informative enough, the principal uses it and no collusion occurs in equilibrium. These contracts, however, are ex post inefficient and are only optimal if the principal can commit not to renegotiate. With renegotiation it is never optimal for the principal to prevent collusion and, at the same time, condition contracts on the signal. In fact, when the signal is informative enough collusion occurs in equilibrium.