Internet Advertising and the Generalized Second-Price Auction: Selling Billions of Dollars Worth of Keywords
研究搜索引擎使用的广义第二价格（GSP）拍卖机制，发现其与VCG机制不同，不存在占优策略均衡，但对应的广义英式拍卖有唯一事后均衡，且收益与VCG占优策略均衡相同。
We investigate the “generalized second-price” (GSP) auction, a new mechanism used by search engines to sell online advertising. Although GSP looks similar to the Vickrey-Clarke-Groves (VCG) mechanism, its properties are very different. Unlike the VCG mechanism, GSP generally does not have an equilibrium in dominant strategies, and truth-telling is not an equilibrium of GSP. To analyze the properties of GSP, we describe the generalized English auction that corresponds to GSP and show that it has a unique equilibrium. This is an ex post equilibrium, with the same payoffs to all players as the dominant strategy equilibrium of VCG.