A Few Bad Apples Spoil the Barrel: An Anti-Folk Theorem for Anonymous Repeated Games with Incomplete Information
研究了匿名重复博弈中可能存在“承诺型”玩家始终采取同一行动的情况，发现若满足平滑条件且存在“两两占优”行动，则该行动几乎总是被采用，从而在匿名随机匹配的囚徒困境中合作不可能，并给出了一般博弈的均衡收益上界。
We study anonymous repeated games where players may be “commitment types” who always take the same action. We establish a stark anti-folk theorem: if the distribution of the number of commitment types satisfies a smoothness condition and the game has a “pairwise dominant” action, this action is almost always taken. This implies that cooperation is impossible in the repeated prisoner's dilemma with anonymous random matching. We also bound equilibrium payoffs for general games. Our bound implies that industry profits converge to zero in linear-demand Cournot oligopoly as the number of firms increases.