Decarolis, FrancescoGoldmanis, MarisPenta, AntonioShakhgildyan, Ksenia2024-02-232024-02-232023Decarolis F, Goldmanis M, Penta A, Shakhgildyan K. Bid coordination in sponsored search auctions: detection methodology and empirical analysis. J Ind Econ. 2023;LXXI(2):570-92. DOI: 10.1111/joie.123310022-1821http://hdl.handle.net/10230/59228Bid delegation to specialized intermediaries is common in internet ad auctions. When the same intermediary bids for 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 bid coordination. When the method is applied to data from auctions held on a major search engine, coordination is detected in 55% of the cases of delegated bidding and the search engine's revenue loss ranges between 5.3% and 10.4%.application/pdfeng© 2023 The Authors. The Journal of Industrial Economics published by The Editorial Board of The Journal of Industrial Economics and John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.info:eu-repo/semantics/articlehttp://dx.doi.org/10.1111/joie.12331info:eu-repo/semantics/openAccess