arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2602.12481cs.GT
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在线广告中的空间互动

Online Advertising with Spatial Interactions

Google Research(谷歌研究院);School of Computer Science, Georgia Tech(佐治亚理工学院计算机学院)

Gagan Aggarwal, Yifan Wang, Mingfei Zhao

AI总结:

本文提出了一种考虑广告位置空间影响的框架,分析了两种广告分配模型,并展示了在不同模型下设计高效诚实机制的复杂性。

摘要:

在线广告平台必须决定如何在有限的屏幕空间上分配多个广告,其中每个广告的效果不仅取决于其自身的放置位置,还取决于附近广告争夺用户注意力的情况。这种空间外部性——源于接近、杂乱或拥挤——可以显著改变福利和收入结果,但现有的拍卖和分配模型通常将广告位视为独立或沿单一维度排列。我们引入了一个新的框架,用于在线广告中的空间外部性,在此框架中,广告的价值取决于其位置以及周围广告的配置。我们将广告位建模为度量空间中的点,并将广告商的价值建模为其出价和由其他显示广告的配置决定的折扣因子之间的函数。在此框架下,我们分析了两种自然模型。对于最近邻模型,其中价值抑制仅取决于最近的邻居广告,我们提出了一种多项式时间算法,能够在一般情况下实现常数近似。我们证明了分配规则是单调的,可以作为诚实机制实现。对于二维欧几里得空间的结构设置,我们提供了PTAS。相比之下,在乘积距离模型中,干扰是沿所有邻居乘积性聚合的,我们建立了强(且几乎紧)的近似难度——除非P=NP,否则不存在多项式时间算法能够实现任何多项式因子近似,通过将Max-Independent-Set问题归约。我们的结果为在广告分配中考虑空间外部性提供了基础,并为在这样的交互下设计高效、诚实的机制提供了依据。

英文摘要:

Online advertising platforms must decide how to allocate multiple ads across limited screen real estate, where each ad's effectiveness depends not only on its own placement but also on nearby ads competing for user attention. Such spatial externalities - arising from proximity, clutter, or crowding - can significantly alter welfare and revenue outcomes, yet existing auction and allocation models typically treat ad slots as independent or ordered along a single dimension. We introduce a new framework for spatial externalities in online advertising, in which the value of an ad depends on both its slot and the configuration of surrounding ads. We model ad slots as points in a metric space, and model an advertiser's value as a function of both their bid and a discount factor determined by the configuration of other displayed ads. Within this framework, we analyze two natural models. For the Nearest-Neighbor model, where the value suppression depends only on the closest neighboring ad, we present a polynomial-time algorithm that achieves a constant approximation for the general case. We show that the allocation rule is monotone and can be implemented as a truthful mechanism. For a structured setting of 2D Euclidean space, we provide a PTAS. In contrast, for the Product-Distance model, where interference is aggregated multiplicatively across all neighbors, we establish a strong (and nearly-tight) hardness of approximation - no polynomial-time algorithm can achieve any polynomial-factor approximation unless P=NP, via a reduction from Max-Independent-Set. Our results provide a foundation for reasoning about spatial externalities in ad allocation and for designing efficient, truthful mechanisms under such interactions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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