Choice screen auctions have been recently deployed in 31 European countries, allowing consumers to choose their preferred search engine on Google’s Android platform instead of being automatically defaulted to Google’s own search engine. The author shows that a seemingly minor detail in the design of these auctions—whether they are conducted on a “per appearance” or a “per install” basis—plays a major role in the mix and characteristics of auction winners, and, consequently, in their expected overall market share. The paper also shows that “per install” auctions distort the incentives of alternative search engines toward extracting as much revenue as possible from each user who installs them, at the expense of lowering the expected number of such users. The distortion becomes worse as the auction gets more competitive and the number of bidders increases. Empirical evidence from Android choice screen auctions conducted in 2020 is consistent with the theoretical results.


Michael Ostrovsky

Stanford University, USA

If you would like to participate and to stay up to date about upcoming presentations, please join our mailing list. You will receive the Zoom link for each talk.

The seminar presentations are scheduled to last 60 minutes: 45 minutes of presentation and 15 minutes for both comments and questions.

We will experiment with various methods for questions: A moderator collects questions during the presentation. Speakers will be encouraged to pause every few slides to allow a gap for questions. The moderator will relay clarification questions or unmute selectively during the talk. Remaining questions will be collected and asked in the discussion period.

Just like with other initiated virtual seminars, these rules are subject to change as we gain experience with how to handle the seminar most efficiently.

The idea for this format was borrowed from the Chamberlain Seminar. Other online seminars can be found at the AEA website.

The Virtual Market Design Seminar is an open online alternative to seminars cancelled due to the COVID-19. Seminars will cover all fields from market design. The seminar presentations are scheduled to last 60 minutes, after 45 minutes of presentation, 15 minutes are for both comments and question.


13.09.2021 | 16:00 - 17:00 (CET)

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