Cartels and bidding rings are often facilitated by intermediaries, who recommend prices/bids to firms and can impose penalties (such as reverting to competitive behavior in future interactions) if these recommendations are not followed. Motivated by such cases, we study correlated equilibria in first-price procurement auctions with complete information, where bidders who disobey their recommendations are penalized. Cartel-optimal profit is greater when more information about submitted bids is disclosed at auction and when the maximum penalty is larger. When only the winner’s identity is disclosed (or the winner’s identity and bid), cartels do not benefit from mediation. Our main result characterizes the cartel-optimal equilibrium with two symmetric bidders when both bids are disclosed. The optimal equilibrium involves extensive randomization and displays tied bids and high winning bids with positive probability, even when the maximum penalty is very small. The stationary mediation schemes we consider are always more profitable for the cartel than bid rotation.

中文翻译：

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调解共谋

卡特尔和投标圈通常是由中间人推动的，中间人向公司推荐价格/出价，如果不遵循这些建议，可以施加处罚（例如在未来的互动中恢复竞争行为）。受此类案例的启发，我们研究了具有完整信息的第一价格采购拍卖中的相关均衡，其中不服​​从其建议的投标人将受到惩罚。当拍卖中披露更多关于提交投标的信息并且最高罚款更大时，卡特尔最优利润更大。当仅披露获胜者的身份（或获胜者的身份和出价）时，卡特尔不会从调解中受益。我们的主要结果描述了当两个投标均被披露时，两个对称投标人的卡特尔最优均衡。最佳均衡涉及广泛的随机化，并以正概率显示平价投标和高中标投标，即使最大罚金非常小。我们考虑的固定调解方案对于卡特尔来说总是比轮换投标更有利可图。