目前,竞标在线广告位是广大广告主宣传其产品的重要途径之一,在线广告位的拍卖已成为搜索引擎企业最主要的盈利手段之一。在国内,广告位拍卖机制的逐利本质诱发了大量的虚假广告,引发了公众的广泛争议;拥有高报价的广告主并不总是带给搜索引擎用户好的用户体验,这些问题已成为搜索引擎亟需解决的重要问题。本文提出了一种既考虑广告主信誉又考虑用户体验的可信有效竞价广告位拍卖机制,定义了在该机制下的对称纳什均衡,给出了广告主的均衡竞价策略,证明了在该均衡下的配置是有效率的。通过与单纯竞价GSP拍卖机制进行比较,我们发现用户的满意度得到了提高,这增加了搜索引擎的竞争优势。此外,本文的拍卖机制不仅有利于促进广告主提高信誉,在提高搜索引擎的长期均衡收益和拍卖效率方面也有一定的优势。通过数值模拟验证了我们的结论。
At present, the bid for online advertising position is an important way for many advertisers to promote their products, and online advertising position auction has become the most important means to make profits for the search engine. In our country, the profit-driven nature of the advertising position auction mechanism causes a large number of false advertising and a wide public controversy. Those advertisers with high bids do not always bring good experience to search engine users. This has become important issues needed to be solved by search engine. In this paper, a creditable effective auction mechanism is presented, considering not only the reputation of advertisers but also the experience of users. A symmetric Nash equilibrium is defined, characterizing the equilibrium bidding strategy of the advertisers and showing that the allocation is effective under our mechanism. Compared with the GSP mechanism of ranking only by bid, it is found that user satisfaction is improved, which increases the competitive advantage of the search engine. In addition, our mechanism may help to improve advertisers' reputation and has advantage in raising search engine's long-term balanced revenue and auction efficiency. Our conclusion is demonstrated by numerical simulation.
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