Sources of Market Power in Web Search: Evidence from a Field Experiment

Hunt Allcott, Juan Castillo, Matthew Gentzkow, Leon Musolff and Tobias Salz

No 33410, NBER Working Papers from National Bureau of Economic Research, Inc

Abstract: We evaluate the economic forces that contribute to Google’s large market share in web search. We develop a model of search engine demand in which consumer choices are influenced by switching costs, quality beliefs, and inattention, and estimate it using a field experiment with US desktop internet users. We find that (i) requiring Google users to make an active choice among search engines increases Bing’s market share by only 1.1 percentage points, implying that switching costs play a limited role; (ii) Google users who accept our payment to try Bing for two weeks update positively about its relative quality, with 33 percent preferring to continue using it; and (iii) after changing the default from Google to Bing, many users do not switch back, consistent with persistent inattention. In our model, correcting beliefs and removing choice frictions would increase Bing’s market share by 15 percentage points and increase consumer surplus by $6 per consumer-year. Policies that expose users to alternative search engines lower Google’s market share more than those requiring active choice. We then use Microsoft search logs to assess the impact of additional data on search result relevance. The results suggest that sharing Google’s click-and-query data with Microsoft may have a limited effect on market shares.

JEL-codes: L4 L86 (search for similar items in EconPapers)
Date: 2025-01
New Economics Papers: this item is included in nep-com, nep-exp, nep-ind, nep-pay and nep-reg
Note: IO LE PR
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.nber.org/papers/w33410.pdf (application/pdf)
Access to the full text is generally limited to series subscribers, however if the top level domain of the client browser is in a developing country or transition economy free access is provided. More information about subscriptions and free access is available at http://www.nber.org/wwphelp.html. Free access is also available to older working papers.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nbr:nberwo:33410

Ordering information: This working paper can be ordered from
http://www.nber.org/papers/w33410
The price is Paper copy available by mail.

Access Statistics for this paper

More papers in NBER Working Papers from National Bureau of Economic Research, Inc National Bureau of Economic Research, 1050 Massachusetts Avenue Cambridge, MA 02138, U.S.A.. Contact information at EDIRC.
Bibliographic data for series maintained by ().