IDEAS home Printed from https://ideas.repec.org/p/cpr/ceprdp/17942.html

Bid Coordination in Sponsored Search Auctions: Detection Methodology and Empirical Analysis

Author

Listed:
  • Decarolis, Francesco
  • Goldmanis, Maris
  • Penta, Antonio
  • Shakhgildyan, Ksenia

Abstract

Bid delegation to specialized intermediaries is common in the auction systems used to sell internet advertising. When the same intermediary concentrates the demand for ad space from competing advertisers, its incentive to coordinate client bids might alter the functioning of the auctions. This study develops a methodology to detect bid coordination, and presents a strategy to estimate a bound on the search engine revenue losses imposed by coordination relative to a counterfactual benchmark of competitive bidding. Using proprietary data from auctions held on a major search engine, coordination is detected in 55 percent of the cases of delegated bidding that we observed, and the associated upper bound on the search engine’s revenue loss ranges between 5.3 and 10.4 percent.

Suggested Citation

  • Decarolis, Francesco & Goldmanis, Maris & Penta, Antonio & Shakhgildyan, Ksenia, 2023. "Bid Coordination in Sponsored Search Auctions: Detection Methodology and Empirical Analysis," CEPR Discussion Papers 17942, C.E.P.R. Discussion Papers.
    • Handle: RePEc:cpr:ceprdp:17942
    as

    Download full text from publisher

    File URL: https://cepr.org/publications/DP17942
    Download Restriction: CEPR Discussion Papers are free to download for our researchers, subscribers and members. If you fall into one of these categories but have trouble downloading our papers, please contact us at subscribers@cepr.org
    ---><---

    As the access to this document is restricted, you may want to look for a different version below or

    for a different version of it.

    Other versions of this item:

    Citations

    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.
    as


    Cited by:

    1. is not listed on IDEAS
    2. Hu Fu & Tao Lin, 2025. "Learning to Coordinate Bidders in Non-Truthful Auctions," Papers 2507.02801, arXiv.org, revised Oct 2025.
    3. Shakhgildyan, Ksenia, 2025. "Nonparametric identification and estimation of the generalized second-price auction," Games and Economic Behavior, Elsevier, vol. 150(C), pages 480-500.
    4. W. Jason Choi & Amin Sayedi, 2024. "Agency Market Power and Information Disclosure in Online Advertising," Marketing Science, INFORMS, vol. 43(6), pages 1279-1298, November.

    More about this item

    Keywords

    ;

    JEL classification:

    • C72 - Mathematical and Quantitative Methods - - Game Theory and Bargaining Theory - - - Noncooperative Games
    • D44 - Microeconomics - - Market Structure, Pricing, and Design - - - Auctions
    • L81 - Industrial Organization - - Industry Studies: Services - - - Retail and Wholesale Trade; e-Commerce

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:cpr:ceprdp:17942. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: the person in charge (email available below). General contact details of provider: https://www.cepr.org .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.