论文标题
有限动作证据游戏中的平衡完善
Equilibrium Refinement in Finite Action Evidence Games
论文作者
论文摘要
证据游戏研究了发件人通过有选择地披露有关世界未知状态的硬证据来说服接收者的情况。证据游戏通常具有多个平衡。 Hart等。 （2017年）建议专注于倾向于真理的均衡，即完美的贝叶斯均衡，在淡淡的情况下，发件人真实地披露，接收者以表面价值进行了隔开披露。他们表明，倾向于真理的平衡是一种扰动游戏的平衡，在该游戏中，发件人对真相的无限奖励。我们表明，当接收器的动作空间是有限的时，倾斜真理的平衡可能不存在，并且不等于扰动游戏的平衡。为了恢复存在，我们引入了一款令人不安的游戏，对接收者的回报有很小的不确定性。随着干扰趋于零，纯净的真实平衡是一系列倾向于真理的平衡的极限。它存在并具有简单的特征。倾斜真实的倾向均衡是扰动游戏的平衡。此外，可净化的真实平衡是接收器的最佳选择，并为接收者提供与最佳确定性机制相同的回报。
Evidence games study situations where a sender persuades a receiver by selectively disclosing hard evidence about an unknown state of the world. Evidence games often have multiple equilibria. Hart et al. (2017) propose to focus on truth-leaning equilibria, i.e., perfect Bayesian equilibria where the sender discloses truthfully when indifferent, and the receiver takes off-path disclosure at face value. They show that a truth-leaning equilibrium is an equilibrium of a perturbed game where the sender has an infinitesimal reward for truth-telling. We show that, when the receiver's action space is finite, truth-leaning equilibrium may fail to exist, and it is not equivalent to equilibrium of the perturbed game. To restore existence, we introduce a disturbed game with a small uncertainty about the receiver's payoff. A purifiable truthful equilibrium is the limit of a sequence of truth-leaning equilibria in the disturbed games as the disturbances converge to zero. It exists and features a simple characterization. A truth-leaning equilibrium that is also purifiable truthful is an equilibrium of the perturbed game. Moreover, purifiable truthful equilibria are receiver optimal and give the receiver the same payoff as the optimal deterministic mechanism.
