Female job seekers are much less likely to be shown adverts on Google for highly paid jobs than men, researchers have found.



The team of researchers from Carnegie Mellon built an automated testing rig called AdFisher that pretended to be a series of male and female job seekers. Their 17,370 fake profiles only visited jobseeker sites and were shown 600,000 adverts which the team tracked and analysed.

The authors of the study wrote: “In particular, we found that males were shown ads encouraging the seeking of coaching services for high paying jobs more than females.”

One experiment showed that Google displayed adverts for a career coaching service for “$200k+” executive jobs 1,852 times to the male group and only 318 times to the female group. Another experiment, in July 2014, showed a similar trend but was not statistically significant.

Google’s ad targeting system is complex, taking into account various factors of personal information, browsing history and internet activity. Critically the fake users started with completely fresh profiles and behaved in the same way, with gender being the only factor that was different and illustrating that the ad targeting for these job adverts was discriminatory.

Discrimination is inherent to advertising

However, the authors of the study admit that the gender discrimination shown is difficult to pin to one factor, due to the complexity of not only Google’s profiling systems, but also of the way advertisers buy and target their adverts using Google.

A Google spokeswoman said: “Advertisers can choose to target the audience they want to reach, and we have policies that guide the type of interest-based ads that are allowed.”



Profiling is inherently discriminatory, as it attempts to treat people differently based on their behaviour and personal information. While that customisation can be useful, showing more relevant ads to users, it can also have negative connotations.

The study authors said: “Male candidates getting more encouragement to seek coaching services for high-paying jobs could further the current gender pay gap. Even if this decision was made solely for economic reasons, it would continue to be discrimination.”



Google allows users to opt out of behavioural advertising and provides a system to see why users were shown ads and to customise their ad settings. But the study suggests that there is a transparency and overt discrimination issue in the wider advertising landscape.

Television, radio and print advertisers have, of course, been practising discrimination for years, pushing ads out with shows or magazines that appeal to a particular gender or demographic.

The difference now is that it is much more obvious in the internet age, and the in-depth profiling that is now possible could make it worse, not better.

Profiling, ad choice, dating and substance abuse

The researchers also investigated whether visiting sites dealing with certain topics, specifically substance abuse, adult content, disabilities, mental disorders and infertility, affected the ads served to the fake profiles.

Only visiting sites dealing with substance abuse and disability created statistically significant results. The researchers found that after visiting substance abuse sites Google’s advert profile page showed no change to the interests listed, but the adverts shown to the user accounts did change, including displaying ads for rehabilitation services from a company called Watershed. The adverts shown to the control group did not include any rehabilitation services.

“One possible reason why Google served Watershed’s ads could be remarketing, a marketing strategy that encourages users to return to previously visited website,” said the authors of the study.

The Watershed site was included in the top 100 substance abuse sites list, which was used as the experimental list of sites to visit by the automated system.

A similar result was shown in testing for disability sites, using a similar methodology. This time the researchers found that Google’s ad interest profile did change for the test group, but that it showed other interests not related to disability.

Ads for mobility devices including a standing wheelchair were shown to the test group 1,076 times but never to the control group. Again the adverts included sites within the top 100 sites concerning disability used during the experiment.

Google has said that it prohibits the targeting of adverts within its “sensitive category policy”, which includes health issues such as substance abuse. It also says that does not allow remarketing within the same sensitive areas.

The researchers also discovered that Google’s ad choices, which allows users to manually remove certain interests from the tracking profiles, had the effect that was desired.

“The ad settings appear to actually give users the ability to avoid ads they

might dislike or find embarrassing,” said the authors.

Removing online dating interests, for instance, stopped online dating ads from appearing within the top five ads served to the test group.

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