COLLUSION IN THE PRESENCE OF EXTERNALITIES*
研究了存在负外部性的拍卖中，合谋投标者的最优投标方案仅具有部分刚性，因为卡特尔既要最大化交易收益，又要最小化销售概率，两者存在冲突。
I examine collusive bidder behavior in auctions with negative externalities and show that the optimal bidding scheme exhibits only partial rigidity. Because of externalities, a cartel not only has incentive to maximize gains from trade but also to minimize the probability of sales. I identify the tension between the two incentives and show that the more rigid the bidding scheme, the higher the possibility of sales. As the extent of externalities increases, the cartel finds it more important to keep a low probability of sales than to minimize payment to the seller. This results in a partially‐rigid optimal collusive bidding scheme.