We consider a variant of the standard Bayesian mechanism, where players evaluate their outcomes and constraints in an ex-ante manner. Such a model captures a major form of modern online advertising where an advertiser is concerned with her/his expected utility over a time period and her/his type may change over time. We are interested in the incentive compatibility (IC) problem of such Bayesian mechanism. Under very mild conditions on the mechanism environments, we give a full characterization of IC via the taxation principle and show, perhaps surprisingly, that such IC mechanisms are fully characterized by the so-called auto-bidding mechanisms, which are pervasively fielded in the online advertising industry.
翻译:我们考虑一种标准巴耶斯机制的变体,在这种机制中,参与者可以事先评估其结果和限制,这种模式可以捕捉一种主要的现代在线广告形式,广告商在一段时间内关心其预期效用,而其类型可能随时间而改变,我们对这种巴耶斯机制的激励兼容性问题感兴趣,在机制环境的非常温和的条件下,我们通过税收原则充分描述IC,并且可能令人惊讶地表明,这种IC机制完全以所谓的自动招标机制为特征,这些机制在网上广告业中普遍存在。