Study: Facebook ad targeting may discriminate—even when advertisers don’t want it to

A new research paper published on Wednesday shows that Facebook’s ad targeting can discriminate by race and gender, even when advertisers request that their ads should be shown to a broad audience.

As you may recall, back in 2016, ProPublica ran ads on Facebook that explicitly excluded targeting users who were black, Hispanic, or other so-called “Ethnic Affinities.” Facebook said it would get rid of the feature in mid 2018. However, that same practice led the U.S. Department of Housing and Urban Development (HUD) to charge Facebook last week with “encouraging, enabling, and causing housing discrimination” in violation of the Fair Housing Act. While the lawyers sort that out, out comes an academic study put together by six researchers from Boston’s Northeastern University, the University of Southern California, and policy group Upturn.

The researchers spent $8,500 running dozens of housing ads on the platform but set the targeting parameters to be “highly inclusive,” according to the paper. Despite their efforts to target every race equally, they found that Facebook’s platform seemed to target by race anyway. For instance, they published ads for houses in North Carolina that were up for either sale or rent. The ads for homes that were for sale were delivered to an audience that was 75% white users. Ads for houses that were for rent were shown to a more mixed demographic.

The researchers also ran identical ads for houses but swapped a white family in one ad with a black family in another. The ad with the white family was shown to 85% white users, while the same ad with the black family was served to an audience of 73% white users, even though the researchers set the ads to be targeted identically. They found similar results when running ads “stereotypically of most interest to black users (e.g., hip-hop),” which were “delivered to over 85% black users,” while country music ads were delivered to over 80% white users, even when targeted identically by the advertiser.

If the study is accurate, it means that even advertisers who want to be inclusive and target all audiences equally may not be able to on the platform. As the researchers wrote: “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.” That said, recently Facebook has said it will limit ad targeting.

We reached out to Facebook for comment and Facebook spokesman Joe Osborne replied, “We stand against discrimination in any form. We’ve announced important changes to our ad targeting tools and know that this is only a first step. We’ve been looking at our ad delivery system and have engaged industry leaders, academics, and civil rights experts on this very topic – and we’re exploring more changes.”