Before the 1970s, people looking for jobs
in the US would open up the “help wanted”
section of their newspapers and see this.
One set of opportunities for women, and one
for men. 
We don’t see job ads like this anymore,
largely because it’s been illegal for decades. 
But also because advertising is now much more
targeted. Instead of one classified page,
we have our social feeds, each crafted by
algorithms for an audience of one. 
So when this ad went out on Facebook and reached
a group of people that was 91% men, those
outside that audience probably didn’t know
it existed.
And the same goes for this ad, which Facebook
displayed for an audience that was 88% women. 
That disparity wasn’t because the advertiser
told Facebook to target users by gender. I
know that because this is the advertiser.
My name is Muhammad Ali, I go by Ali.
He’s part of a research group at Northeastern
University that has spent thousands of dollars
buying ads to try to figure out who Facebook
will show them to, and why.
If an ad shows up on your Facebook or Instagram
feed, there are two parties that decided you
should see it. First, the advertiser included
you in their target audience, either by uploading
a list of specific email addresses, phone
numbers, or previous visitors to their website,
Or by choosing from thousands of attributes
that facebook offers, like Californians, under
40 who like basketball.
Second, Facebook decided who in that pool
would actually see the ad through an automated
calculation based in part on what they know
about you.
It’s that second step that Ali and his colleagues
wanted to study. If they uploaded a list of
randomly-generated American phone numbers,
and then turned off all the targeting except
adults in the US, who would Facebook deliver
the ad to?
So you set up a bodybuilding ad and a cosmetic
ad and said we don't wanna target this any
further than the random phone numbers that
we put in. Right? And then what were your
results? When Facebook started telling you
who was actually seeing this ad, what did
they tell you?
So, yeah, immediately, like we sort of expected
that the body building ad was more relevant
to men. And that's exactly what we saw. I
think somewhere close to 80 to 85 percent
of the audience was just men.
And the link that we advertise to elle.com
about the makeup kits that you could buy that
went primarily to women.
They were able to collect the results of the
ads over time so they knew the gender skew
was there early on, suggesting that it wasn’t
introduced by user behavior.
Their experiment showed that Facebook automatically
analyzes the content of an ad to compare it
to a user’s interests.
How do they know what the user cares about?
Well they have data from your profile and
everything you and your friends have done
on facebook and instagram, as well as websites
you’ve visited, things you’ve purchased,
apps you’ve installed, your location, your
devices, and more. 
All this information fuels automated predictions
about whether you are likely to engage with
any given ad. And that prediction influences
whether the ad shows up on your feed at all.
You can get a sense of what Facebook thinks
you’re interested in on your Ad Preferences
page. Or your Ad Interests on instagram.
Notice how some of these interests could correlate
with your gender, your age, your income level,
or your race.
And then you wanted to look at race. But it
sounds like Facebook does not give you data
on the race of people that are seeing an ad.
So how do you study that?
That was one of the harder things to do. We
thought we could use a different custom audience.
Instead of random phone numbers. We could
take voter records from North Carolina, which
are public, and they have the race of the
person registered as well.
Then they bought ads for Rolling Stone articles
that were either about country albums, hip
hop albums, or general top 30 albums and targeted
an equal number of white and Black users.
And it was surprising how much the skew to
the Black users was for the hip bag versus
the country and the top 30.
Facebook’s algorithms are trained to not
show people ads they won’t be interested
in. 
But there may be cases when we’re not comfortable
with Facebook making those predictions.
One study by Ali and his colleagues investigated
how this plays out with political ads and
found that despite targeting the same audiences,
using the same goal, bidding strategy, and
budget,
an ad pointing to Bernie Sanders’ site went
to mostly Democrats and an ad for Trump went
to mostly Republicans. 
It cost 1.5 times more for an ad linking to
Sanders’ site to reach the same number of
conservatives as a Trump ad. Because Facebook
subsidizes what they consider to be “relevant”
ads.
And then we move on to housing and employment
ads, and these are considered sort of a different
category. Why is that? Because these are legally protected. For example, housing ads are protected by
the Fair Housing Act. An advertiser cannot discriminate in those
cases. At that point, you're excluding someone
from a life opportunity which becomes much
more problematic.
Because it's actually a legal violation that's
at stake? Possibly?
Possibly.
Facebook allows advertisers to exclude certain
ethnic groups from seeing an ad.
Dozens of employers placing job ads on Facebook
that discriminate against older workers.
Facebook is revamping its targeted advertisements
after settling lawsuits with civil rights
groups.
In response to criticism and several lawsuits,
Facebook has been removing some of the targeting
attributes that an advertiser could use to
discriminate against demographic groups, and
is paying special attention to ads related
to employment, housing, and credit. 
But the role that the ad delivery system plays
remains unsolved.
When Ali and his team tested out ads for job
openings in different industries, without
targeting any demographic groups, facebook
generated some skewed audiences. The lumber
industry post went to mostly men. The cleaner
post went to mostly women.
The taxi driver ads that we ran, basically
seventy five percent of the audience was black
users.
These results don’t mean that Facebook is
directly basing their predictions on our gender
or race. Instead it looks for patterns in
all of our user data.
Maybe people who shop at a men’s clothing
site and like joe rogan are less likely to
click on an ad for a job teaching preschool.
Maybe your data is similar to theirs and so
they predict you also wont click on that ad
either.
Instead they show it to someone who likes
skincare and feminism. And if that person
clicks, the system gets a new data point affirming
its prediction.
A complaint filed by the US Department of
Housing and Urban Development states that
this process “inevitably recreates groupings
defined by their protected class.” They
said that Facebook’s ad delivery system
“prevents advertisers who want to reach
a broad audience of users from doing so.”
According to a report by ProPublica, a construction
workers’ union wanted to recruit diverse
candidates for its apprenticeship program,
so they created ads featuring women, but found
that Facebook still showed its them to mostly men.
And wouldn't any ad targeting system with
sort of sufficiently rich data about people
have this kind of effect?
Well, we believe so, because a lot of these
things, for example, custom audiences on all
of these targeting features --they’re industry
practice. They that also in Google's or Linkedin’s or
Twitter's advertising platform. So the general ethos of how these systems work is the same.
It’s a question that the industry as a whole hasn’t answered:
When exactly is it unacceptable
for an algorithm to decide that relevant audiences
are segregated ones?
