Optimal Collusion with Private Information
分析无限重复伯特兰博弈中的合谋，企业私下观察成本冲击，通过历史依赖的市场份额再分配实现最优合谋利润，并探讨沟通与侧支付的作用。
We analyze collusion in an infinitely repeated Bertrand game, where prices are publicly observed and each firm receives a privately observed, i.i.d. cost shock in each period. Productive efficiency is possible only if high-cost firms relinquish market share. In the most profitable collusive schemes, firms implement productive efficiency, and high-cost firms are favored with higher expected market share in future periods. If types are discrete, there exists a discount factor strictly less than one above which first-best profits can be attained using history-dependent reallocation of market share between equally efficient firms. We also analyze the role of communication and side-payments. 1.