Cited by 268Ethics and Social Impacts of AIPrivacy, Security, and Data ProtectionNames, Identity, and Discrimination Research

The DOI matches its Crossref record; 45 of the 45 references it cites were found in a registry or an index; 7 of the 33 sources its claims cite were checked for support.

Discrimination through Optimization

Open access
Ali, Muhammad, Sapiezynski, Piotr, Bogen, Miranda, Korolova, Aleksandra, Mislove, Alan, Rieke, Aaron·2019·Proceedings of the ACM on Human-Computer Interaction

Abstract

The enormous financial success of online advertising platforms is partially due to the precise targeting features they offer. Although researchers and journalists have found many ways that advertisers can target---or exclude---particular groups of users seeing their ads, comparatively little attention has been paid to the implications of the platform's ad delivery process, comprised of the platform's choices about which users see which ads. It has been hypothesized that this process can "skew" ad delivery in ways that the advertisers do not intend, making some users less likely than others to see particular ads based on their demographic characteristics. In this paper, we demonstrate that such skewed delivery occurs on Facebook, due to market and financial optimization effects as well as the platform's own predictions about the "relevance" of ads to different groups of users. We find that both the advertiser's budget and the content of the ad each significantly contribute to the skew of Facebook's ad delivery. Critically, we observe significant skew in delivery along gender and racial lines for "real" ads for employment and housing opportunities despite neutral targeting parameters. Our results demonstrate previously unknown mechanisms that can lead to potentially discriminatory ad delivery, even when advertisers set their targeting parameters to be highly inclusive. This underscores the need for policymakers and platforms to carefully consider the role of the ad delivery optimization run by ad platforms themselves---and not just the targeting choices of advertisers---in preventing discrimination in digital advertising.

Overview

Integrity signals

Registry

Crossref · 10.1145/3359301

Cites

45 of 45 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

7 of 33 cited sources checked · 2 supported · 0 flagged · accuracy not yet measured

  • Probably not a substantial claim. 33
  • It may state two separate claims as one. 46
  • The quote only partly states this claim. 4
68 of 68
  • The paper relies on this without support.

    Comparatively little attention has been paid to the implications of the platform's ad delivery process.

    “Although researchers and journalists have found many ways that advertisers can target-or excludeparticular groups of users seeing their ads, comparatively little attention has been paid to the implications of the platform's ad delivery process, comprised of the platform's choices about which users see which ads.”
  • The paper relies on this without support.

    Prior to this work, it was not known whether market effects and optimization effects resulted in skewed ad delivery in real-world advertising platforms.

    “Prior to this work, although hypothesized [25,52,72], it was not known whether the above factors resulted in skewed ad delivery in real-world advertising platforms.”
  • The paper relies on this without support.

    The exact mechanisms by which platforms address ad delivery issues are not well-described or documented by the platforms.

    “The exact mechanisms by which these issues are addressed are not well-described or documented by the platforms.”
  • The authors state this as an assumption.

    DMAs are a valid proxy for race.

    “Because we selected DMAs to be a proxy for race, we can use the results to infer which custom audience they were originally in, allowing us to determine the racial makeup of the audience who saw (and clicked on) the ad.”
  • The paper relies on this without support.

    Users' self-reported race in voter records is accurate.

    “Further, when considering racial bias, we use the self-reported information from voter records.”
  • The paper relies on this without support.

    The experimental controls (same time, budget, targeting) are sufficient to rule out other explanations for the observed delivery skew.

    “When running these experiments, we keep the ad creative and targeted audience constant, only changing the bidding strategy to give Facebook different daily limits (thus, any ad delivery differences can be attributed to the budget alone).”
  • The paper relies on this without support.

    The entertainment ads' stereotypical associations (country music = white, hip-hop = Black) are valid.

    “top country music (stereotypically of interest mostly to white users), and top hip-hop albums (stereotypically of interest mostly to Black users).”
  • The paper relies on this without support.

    The housing ads' implied cost through wording and image is perceived as intended.

    “In each ad, the cost is implied through wording of the ad as well as the accompanying image.”
  • The paper relies on this without support.

    In traditional media, advertisers can purposefully advertise to a wide and diverse audience and be assured that their ads will reach that audience.

    “when advertising in traditional media, the advertiser has the ability to purposefully advertise to a wide and diverse audience, and be assured that their ads will reach that audience.”
  • The paper relies on this without support.

    U.S. federal law prohibits discrimination in the marketing of housing, employment and credit opportunities.

    “U.S. federal law prohibits discrimination in the marketing of housing, employment and credit opportunities.”
  • The paper relies on this without support.

    Section 230 of the Communications Decency Act (CDA) provides broad legal immunity for internet platforms acting as publishers of third-party content.

    “Section 230 of the Communications Decency Act (CDA) provides broad legal immunity for internet platforms acting as publishers of third-party content.”
  • The paper relies on this without support.

    Facebook's existing ad transparency efforts are not yet sufficient to allow researchers to analyze the impact of ad delivery in the real world.

    “Facebook's existing ad transparency efforts are not yet sufficient to allow researchers to analyze the impact of ad delivery in the real world.”
  • The paper relies on this without support.

    Different users are valued differently by advertisers.

    “different users are valued differently by advertisers”
  • The paper relies on this without support.

    In a setting of limited user attention, there is a tension between providing a useful service for users and advertisers, fair ad delivery, and the platform's own revenue goals.

    “which, in a setting of limited user attention, leads to a tension between providing a useful service for users and advertisers, fair ad delivery, and the platform's own revenue goals.”
14 of 14

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Image transparency is reported as opacity

    Minor

    The methods say the test images had 98% opacity, but elsewhere describe them as having 98% transparency. Those are opposite settings: at 98% opacity, the original images would remain readily visible, undermining the stated basis of the invisible-image experiment.

  • In-text citation points to a different study

    Minor

    The paper attributes the earlier ad-delivery finding to Lambrecht et al. at reference [52], but bibliography entry 52 is by Kulshrestha et al.; the Lambrecht and Tucker study is entry 53. This reflects a mismatch between the in-text citation and the paper's own reference list.

2 of 2

Citations

Cites

Flagged first, then by citations

Show all 38 references

Research works printed but not linked: 4

  1. Joy Buolamwini and Timnit Gebru . 2018 . Gender Shades: Intersectional Accuracy Disparities In Commercial Gender Classification. In Conference on Fairness, Accountability, and Transparency . New York, New York, USA. Joy Buolamwini and Timnit Gebru. 2018. Gender Shades: Intersectional Accuracy Disparities In Commercial Gender Classification. In Conference on Fairness, Accountability, and Transparency. New York, New York, USA.
  2. Robert J. Cabin and Randall J. Mitchell . 2000 . To Bonferroni Or Not To Bonferroni: When And How Are The Questions . Bulletin of the Ecological Society of America , Vol. 81 , 3 (2000), 246 -- 248 . Robert J. Cabin and Randall J. Mitchell. 2000. To Bonferroni Or Not To Bonferroni: When And How Are The Questions. Bulletin of the Ecological Society of America, Vol. 81, 3 (2000), 246--248.
  3. Avijit Ghosh , Giridhari Venkatadri , and Alan Mislove . 2019 . Analyzing Facebook Political Advertisers' Targeting. In Workshop on Technology and Consumer Protection . San Francisco, California, USA. Avijit Ghosh, Giridhari Venkatadri, and Alan Mislove. 2019. Analyzing Facebook Political Advertisers' Targeting. In Workshop on Technology and Consumer Protection. San Francisco, California, USA.
  4. Christian Sandvig , Kevin Hamilton , Karrie Karahalios , and Cedric Langbort . 2014 . Auditing Algorithms: Research Methods For Detecting Discrimination On Internet Platforms. In International Communication Association Conference. Christian Sandvig, Kevin Hamilton, Karrie Karahalios, and Cedric Langbort. 2014. Auditing Algorithms: Research Methods For Detecting Discrimination On Internet Platforms. In International Communication Association Conference.

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Metadata

Authors
Ali, M., Sapiezynski, P., Bogen, M., Korolova, A., Mislove, A., & Rieke, A.
Affiliations
  • Northeastern University (US)
  • Northeastern University, Boston, MA, USA
  • Upturn, Inc., Washington, DC, USA
  • University of Southern California (US)
  • Upturn, Washington, DC, USA
Venue
Proceedings of the ACM on Human-Computer Interaction
Published
2019-11-07
Volume
3
Issue
CSCW
Pages
1-30
ISSN
2573-0142 (ISSN-L)
OpenAlex
W4288086175
Cited by
268
References
38
Citations by year
2026: 32 · 2025: 38 · 2024: 33 · 2023: 49 · 2022: 55 · 2021: 41 · 2020: 18
FWCI
49.82
Type
journal article
Language
en
Open access
Locations
Proceedings of the ACM on Human-Computer Interaction (publishedVersion)
Funders
  • Data Transparency Lab (-)
  • National Science Foundation (CNS-1616234)
Topics
  • Physical Sciences › Computer Science › Artificial Intelligence › Ethics and Social Impacts of AI
  • Social Sciences › Sociology and Political Science › Privacy, Security, and Data Protection
  • Social Sciences › Sociology and Political Science › Names, Identity, and Discrimination Research
Keywords
online advertising, algorithmic discrimination, Facebook, targeted advertising, gender discrimination, racial discrimination, ad relevance

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