Revenue Guarantees in Sponsored Search Auctions
Revenue Guarantees in Sponsored Search Auctions
复制标题
赞助搜索拍卖中的收入保证
DOI：
--
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
M. Kyropoulou
中科院分区：
文献类型：
--
作者：
I. Caragiannis;C. Kaklamanis;P. Kanellopoulos;M. Kyropoulou
赞助搜索拍卖是搜索引擎的主要收入来源。在这样的拍卖中，一组效用最大化的广告商竞争一组广告位。广告商的广告位分配取决于他们提交的出价；这些出价可能与广告商对时段的真实估价不同。著名的 VCG 拍卖机制的变体保证广告商诚实行事，并在温和的假设下实现收入或社会福利最大化。尽管如此，赞助搜索行业主要使用广义二次价格 (GSP) 拍卖；众所周知，这些拍卖在社会福利和收入方面是不真实且次优的。为了解释这一传统，我们研究了贝叶斯设置，其中广告商的估值是独立于正则概率分布得出的。在这种情况下，Myerson (1981) 的工作众所周知，最优收入是通过 VCG 机制获得的，并且特定的底价取决于概率分布。我们表明，通过适当设定底价，普惠制拍卖引起的任何贝叶斯-纳什博弈均衡的收入至多是最优收入的一小部分，改善了 Lucier、Paes Leme 和 Tardos (2012) 的最新结果。我们的分析基于贝叶斯-纳什均衡条件和正则概率分布的性质。
Sponsored search auctions are the main source of revenue for search engines. In such an auction, a set of utility-maximizing advertisers compete for a set of ad slots. The assignment of advertisers to slots depends on bids they submit; these bids may be different than the true valuations of the advertisers for the slots. Variants of the celebrated VCG auction mechanism guarantee that advertisers act truthfully and, under mild assumptions, lead to revenue or social welfare maximization. Still, the sponsored search industry mostly uses generalized second price (GSP) auctions; these auctions are known to be non-truthful and suboptimal in terms of social welfare and revenue. In an attempt to explain this tradition, we study a Bayesian setting where the valuations of advertisers are drawn independently from a regular probability distribution. In this setting, it is well known by the work of Myerson (1981) that the optimal revenue is obtained by the VCG mechanism with a particular reserve price that depends on the probability distribution. We show that by appropriately setting the reserve price, the revenue over any Bayes-Nash equilibrium of the game induced by the GSP auction is at most a small constant fraction of the optimal revenue, improving recent results of Lucier, Paes Leme, and Tardos (2012). Our analysis is based on the Bayes-Nash equilibrium conditions and on the properties of regular probability distributions .