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Mediators in position auctions

Published: 11 June 2007 Publication History

Abstract

A mediator is a reliable entity, which can play on behalf of agents in a given game. A mediator however can not enforce the use of its services, and each agent is free to participate in the game directly. In this paper we introduce a study of mediators for games with incomplete information, and apply it to the context of position auctions, a central topic in electronic commerce. VCG position auctions, which are currently not used in practice, possess somenice theoretical properties, such as the optimization of social surplus and having dominant strategies. These properties may not be satisfied by current position auctions and their variants. We therefore concentrate on the search for mediators that will allow to transform current position auctions into VCG position auctions. We require that accepting the mediator services, and reporting honestly to the mediator, will form an ex post equilibrium, which satisfiesthe following rationality condition: an agent's payoff can not be negative regardless of the actions taken by the agents who did not choose the mediator's services, or by the agents who report false types to the mediator. We prove the existence of such desired mediators for the next-price (Google-like) position auctions, as well as for a richer class of position auctions, including k-price position auctions, k>1. For k=1, the self-price position auction, we show that the existence of such mediator depends on the tie breaking rule used in the auction.

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Cited By

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  • (2016)Complexity and Algorithms of K-implementationProceedings of the 2016 International Conference on Autonomous Agents & Multiagent Systems10.5555/2936924.2936931(5-13)Online publication date: 9-May-2016
  • (2016)Mechanism Design for Mixed BiddersProceedings of the 25th International Conference on World Wide Web10.1145/2872427.2882983(215-225)Online publication date: 11-Apr-2016
  • (2012)Keywords tender price selected in the generalized second price position auction2012 24th Chinese Control and Decision Conference (CCDC)10.1109/CCDC.2012.6244125(816-820)Online publication date: May-2012
  • Show More Cited By

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    cover image ACM Conferences
    EC '07: Proceedings of the 8th ACM conference on Electronic commerce
    June 2007
    384 pages
    ISBN:9781595936530
    DOI:10.1145/1250910
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    Publication History

    Published: 11 June 2007

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    Author Tags

    1. auction
    2. equilibrium
    3. mediator

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    EC07: ACM Conference on Electronic Commerce
    June 11 - 15, 2007
    California, San Diego, USA

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    Overall Acceptance Rate 664 of 2,389 submissions, 28%

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    Cited By

    View all
    • (2016)Complexity and Algorithms of K-implementationProceedings of the 2016 International Conference on Autonomous Agents & Multiagent Systems10.5555/2936924.2936931(5-13)Online publication date: 9-May-2016
    • (2016)Mechanism Design for Mixed BiddersProceedings of the 25th International Conference on World Wide Web10.1145/2872427.2882983(215-225)Online publication date: 11-Apr-2016
    • (2012)Keywords tender price selected in the generalized second price position auction2012 24th Chinese Control and Decision Conference (CCDC)10.1109/CCDC.2012.6244125(816-820)Online publication date: May-2012
    • (2009)User modeling in position auctionsProceedings of The 8th International Conference on Autonomous Agents and Multiagent Systems - Volume 110.5555/1558013.1558050(273-280)Online publication date: 10-May-2009
    • (2009)Computational analysis of perfect-information position auctionsProceedings of the 10th ACM conference on Electronic commerce10.1145/1566374.1566382(51-60)Online publication date: 6-Jul-2009
    • (2009)Nash Bargaining Based Ad Networks for Sponsored Search AuctionsProceedings of the 2009 IEEE Conference on Commerce and Enterprise Computing10.1109/CEC.2009.46(170-175)Online publication date: 20-Jul-2009
    • (2009)Strong mediated equilibriumArtificial Intelligence10.1016/j.artint.2008.10.005173:1(180-195)Online publication date: 1-Jan-2009
    • (2009)Mediated Equilibria in Load-Balancing GamesProceedings of the 5th International Workshop on Internet and Network Economics10.1007/978-3-642-10841-9_60(591-599)Online publication date: 9-Dec-2009
    • (2008)A Nash bargaining approach to retention enhancing bid optimization in sponsored search auctions with discrete bids2008 IEEE International Conference on Automation Science and Engineering10.1109/COASE.2008.4626517(1007-1012)Online publication date: Aug-2008

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