TED2017
Cathy O'Neil: The era of blind faith in big data must end
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Algorithms decide who gets a loan, who gets a job interview, who gets insurance and much more -- but they don't automatically make things fair. Mathematician and data scientist Cathy O'Neil coined a term for algorithms that are secret, important and harmful: "weapons of math destruction." Learn more about the hidden agendas behind the formulas.
Cathy O'Neil - Mathematician, data scientist
Data skeptic Cathy O’Neil uncovers the dark secrets of big data, showing how our "objective" algorithms could in fact reinforce human bias. Full bio
Data skeptic Cathy O’Neil uncovers the dark secrets of big data, showing how our "objective" algorithms could in fact reinforce human bias. Full bio
Double-click the English transcript below to play the video.
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Algorithms are everywhere.
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They sort and separate
the winners from the losers.
the winners from the losers.
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The winners get the job
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or a good credit card offer.
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The losers don't even get an interview
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or they pay more for insurance.
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We're being scored with secret formulas
that we don't understand
that we don't understand
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that often don't have systems of appeal.
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That begs the question:
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What if the algorithms are wrong?
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To build an algorithm you need two things:
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you need data, what happened in the past,
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and a definition of success,
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the thing you're looking for
and often hoping for.
and often hoping for.
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You train an algorithm
by looking, figuring out.
by looking, figuring out.
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The algorithm figures out
what is associated with success.
what is associated with success.
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What situation leads to success?
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Actually, everyone uses algorithms.
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They just don't formalize them
in written code.
in written code.
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Let me give you an example.
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I use an algorithm every day
to make a meal for my family.
to make a meal for my family.
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The data I use
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is the ingredients in my kitchen,
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the time I have,
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the ambition I have,
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and I curate that data.
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I don't count those little packages
of ramen noodles as food.
of ramen noodles as food.
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(Laughter)
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My definition of success is:
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a meal is successful
if my kids eat vegetables.
if my kids eat vegetables.
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It's very different
from if my youngest son were in charge.
from if my youngest son were in charge.
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He'd say success is if
he gets to eat lots of Nutella.
he gets to eat lots of Nutella.
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But I get to choose success.
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I am in charge. My opinion matters.
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That's the first rule of algorithms.
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Algorithms are opinions embedded in code.
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It's really different from what you think
most people think of algorithms.
most people think of algorithms.
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They think algorithms are objective
and true and scientific.
and true and scientific.
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That's a marketing trick.
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It's also a marketing trick
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to intimidate you with algorithms,
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to make you trust and fear algorithms
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because you trust and fear mathematics.
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A lot can go wrong when we put
blind faith in big data.
blind faith in big data.
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This is Kiri Soares.
She's a high school principal in Brooklyn.
She's a high school principal in Brooklyn.
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In 2011, she told me
her teachers were being scored
her teachers were being scored
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with a complex, secret algorithm
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called the "value-added model."
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I told her, "Well, figure out
what the formula is, show it to me.
what the formula is, show it to me.
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I'm going to explain it to you."
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She said, "Well, I tried
to get the formula,
to get the formula,
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but my Department of Education contact
told me it was math
told me it was math
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and I wouldn't understand it."
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It gets worse.
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The New York Post filed
a Freedom of Information Act request,
a Freedom of Information Act request,
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got all the teachers' names
and all their scores
and all their scores
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and they published them
as an act of teacher-shaming.
as an act of teacher-shaming.
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When I tried to get the formulas,
the source code, through the same means,
the source code, through the same means,
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I was told I couldn't.
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I was denied.
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I later found out
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that nobody in New York City
had access to that formula.
had access to that formula.
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No one understood it.
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Then someone really smart
got involved, Gary Rubenstein.
got involved, Gary Rubenstein.
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He found 665 teachers
from that New York Post data
from that New York Post data
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that actually had two scores.
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That could happen if they were teaching
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seventh grade math and eighth grade math.
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He decided to plot them.
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Each dot represents a teacher.
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(Laughter)
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What is that?
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(Laughter)
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That should never have been used
for individual assessment.
for individual assessment.
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It's almost a random number generator.
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(Applause)
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But it was.
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This is Sarah Wysocki.
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She got fired, along
with 205 other teachers,
with 205 other teachers,
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from the Washington, DC school district,
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even though she had great
recommendations from her principal
recommendations from her principal
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and the parents of her kids.
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I know what a lot
of you guys are thinking,
of you guys are thinking,
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especially the data scientists,
the AI experts here.
the AI experts here.
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You're thinking, "Well, I would never make
an algorithm that inconsistent."
an algorithm that inconsistent."
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But algorithms can go wrong,
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even have deeply destructive effects
with good intentions.
with good intentions.
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And whereas an airplane
that's designed badly
that's designed badly
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crashes to the earth and everyone sees it,
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an algorithm designed badly
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can go on for a long time,
silently wreaking havoc.
silently wreaking havoc.
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This is Roger Ailes.
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(Laughter)
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He founded Fox News in 1996.
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More than 20 women complained
about sexual harassment.
about sexual harassment.
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They said they weren't allowed
to succeed at Fox News.
to succeed at Fox News.
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He was ousted last year,
but we've seen recently
but we've seen recently
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that the problems have persisted.
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That begs the question:
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What should Fox News do
to turn over another leaf?
to turn over another leaf?
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Well, what if they replaced
their hiring process
their hiring process
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with a machine-learning algorithm?
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That sounds good, right?
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Think about it.
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The data, what would the data be?
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A reasonable choice would be the last
21 years of applications to Fox News.
21 years of applications to Fox News.
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Reasonable.
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What about the definition of success?
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Reasonable choice would be,
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well, who is successful at Fox News?
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I guess someone who, say,
stayed there for four years
stayed there for four years
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and was promoted at least once.
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Sounds reasonable.
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And then the algorithm would be trained.
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It would be trained to look for people
to learn what led to success,
to learn what led to success,
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what kind of applications
historically led to success
historically led to success
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by that definition.
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Now think about what would happen
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if we applied that
to a current pool of applicants.
to a current pool of applicants.
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It would filter out women
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because they do not look like people
who were successful in the past.
who were successful in the past.
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Algorithms don't make things fair
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if you just blithely,
blindly apply algorithms.
blindly apply algorithms.
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They don't make things fair.
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They repeat our past practices,
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our patterns.
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They automate the status quo.
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That would be great
if we had a perfect world,
if we had a perfect world,
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but we don't.
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And I'll add that most companies
don't have embarrassing lawsuits,
don't have embarrassing lawsuits,
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but the data scientists in those companies
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are told to follow the data,
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to focus on accuracy.
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Think about what that means.
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Because we all have bias,
it means they could be codifying sexism
it means they could be codifying sexism
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or any other kind of bigotry.
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Thought experiment,
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because I like them:
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an entirely segregated society --
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racially segregated, all towns,
all neighborhoods
all neighborhoods
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and where we send the police
only to the minority neighborhoods
only to the minority neighborhoods
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to look for crime.
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The arrest data would be very biased.
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What if, on top of that,
we found the data scientists
we found the data scientists
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and paid the data scientists to predict
where the next crime would occur?
where the next crime would occur?
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Minority neighborhood.
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Or to predict who the next
criminal would be?
criminal would be?
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A minority.
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The data scientists would brag
about how great and how accurate
about how great and how accurate
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their model would be,
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and they'd be right.
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Now, reality isn't that drastic,
but we do have severe segregations
but we do have severe segregations
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in many cities and towns,
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and we have plenty of evidence
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of biased policing
and justice system data.
and justice system data.
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And we actually do predict hotspots,
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places where crimes will occur.
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And we do predict, in fact,
the individual criminality,
the individual criminality,
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the criminality of individuals.
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The news organization ProPublica
recently looked into
recently looked into
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one of those "recidivism risk" algorithms,
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as they're called,
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being used in Florida
during sentencing by judges.
during sentencing by judges.
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Bernard, on the left, the black man,
was scored a 10 out of 10.
was scored a 10 out of 10.
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Dylan, on the right, 3 out of 10.
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10 out of 10, high risk.
3 out of 10, low risk.
3 out of 10, low risk.
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They were both brought in
for drug possession.
for drug possession.
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They both had records,
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but Dylan had a felony
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but Bernard didn't.
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This matters, because
the higher score you are,
the higher score you are,
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the more likely you're being given
a longer sentence.
a longer sentence.
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What's going on?
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Data laundering.
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It's a process by which
technologists hide ugly truths
technologists hide ugly truths
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inside black box algorithms
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and call them objective;
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call them meritocratic.
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When they're secret,
important and destructive,
important and destructive,
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I've coined a term for these algorithms:
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"weapons of math destruction."
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(Laughter)
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(Applause)
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They're everywhere,
and it's not a mistake.
and it's not a mistake.
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These are private companies
building private algorithms
building private algorithms
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for private ends.
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Even the ones I talked about
for teachers and the public police,
for teachers and the public police,
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those were built by private companies
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and sold to the government institutions.
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They call it their "secret sauce" --
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that's why they can't tell us about it.
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It's also private power.
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They are profiting for wielding
the authority of the inscrutable.
the authority of the inscrutable.
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Now you might think,
since all this stuff is private
since all this stuff is private
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and there's competition,
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maybe the free market
will solve this problem.
will solve this problem.
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It won't.
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There's a lot of money
to be made in unfairness.
to be made in unfairness.
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Also, we're not economic rational agents.
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We all are biased.
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We're all racist and bigoted
in ways that we wish we weren't,
in ways that we wish we weren't,
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in ways that we don't even know.
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We know this, though, in aggregate,
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because sociologists
have consistently demonstrated this
have consistently demonstrated this
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with these experiments they build,
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where they send a bunch
of applications to jobs out,
of applications to jobs out,
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equally qualified but some
have white-sounding names
have white-sounding names
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and some have black-sounding names,
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and it's always disappointing,
the results -- always.
the results -- always.
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So we are the ones that are biased,
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and we are injecting those biases
into the algorithms
into the algorithms
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by choosing what data to collect,
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like I chose not to think
about ramen noodles --
about ramen noodles --
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I decided it was irrelevant.
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But by trusting the data that's actually
picking up on past practices
picking up on past practices
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and by choosing the definition of success,
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how can we expect the algorithms
to emerge unscathed?
to emerge unscathed?
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We can't. We have to check them.
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We have to check them for fairness.
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The good news is,
we can check them for fairness.
we can check them for fairness.
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Algorithms can be interrogated,
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and they will tell us
the truth every time.
the truth every time.
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And we can fix them.
We can make them better.
We can make them better.
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I call this an algorithmic audit,
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and I'll walk you through it.
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First, data integrity check.
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For the recidivism risk
algorithm I talked about,
algorithm I talked about,
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a data integrity check would mean
we'd have to come to terms with the fact
we'd have to come to terms with the fact
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that in the US, whites and blacks
smoke pot at the same rate
smoke pot at the same rate
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but blacks are far more likely
to be arrested --
to be arrested --
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four or five times more likely,
depending on the area.
depending on the area.
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What is that bias looking like
in other crime categories,
in other crime categories,
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and how do we account for it?
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Second, we should think about
the definition of success,
the definition of success,
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audit that.
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Remember -- with the hiring
algorithm? We talked about it.
algorithm? We talked about it.
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Someone who stays for four years
and is promoted once?
and is promoted once?
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Well, that is a successful employee,
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but it's also an employee
that is supported by their culture.
that is supported by their culture.
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That said, also it can be quite biased.
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We need to separate those two things.
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We should look to
the blind orchestra audition
the blind orchestra audition
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as an example.
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That's where the people auditioning
are behind a sheet.
are behind a sheet.
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What I want to think about there
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is the people who are listening
have decided what's important
have decided what's important
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and they've decided what's not important,
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and they're not getting
distracted by that.
distracted by that.
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When the blind orchestra
auditions started,
auditions started,
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the number of women in orchestras
went up by a factor of five.
went up by a factor of five.
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Next, we have to consider accuracy.
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This is where the value-added model
for teachers would fail immediately.
for teachers would fail immediately.
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No algorithm is perfect, of course,
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so we have to consider
the errors of every algorithm.
the errors of every algorithm.
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How often are there errors,
and for whom does this model fail?
and for whom does this model fail?
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What is the cost of that failure?
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And finally, we have to consider
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the long-term effects of algorithms,
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the feedback loops that are engendering.
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That sounds abstract,
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but imagine if Facebook engineers
had considered that
had considered that
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before they decided to show us
only things that our friends had posted.
only things that our friends had posted.
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I have two more messages,
one for the data scientists out there.
one for the data scientists out there.
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Data scientists: we should
not be the arbiters of truth.
not be the arbiters of truth.
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We should be translators
of ethical discussions that happen
of ethical discussions that happen
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in larger society.
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(Applause)
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And the rest of you,
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the non-data scientists:
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this is not a math test.
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This is a political fight.
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We need to demand accountability
for our algorithmic overlords.
for our algorithmic overlords.
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(Applause)
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The era of blind faith
in big data must end.
in big data must end.
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Thank you very much.
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(Applause)
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ABOUT THE SPEAKER
Cathy O'Neil - Mathematician, data scientistData skeptic Cathy O’Neil uncovers the dark secrets of big data, showing how our "objective" algorithms could in fact reinforce human bias.
Why you should listen
In 2008, as a hedge-fund quant, mathematician Cathy O’Neil saw firsthand how really really bad math could lead to financial disaster. Disillusioned, O’Neil became a data scientist and eventually joined Occupy Wall Street’s Alternative Banking Group.
With her popular blog mathbabe.org, O’Neil emerged as an investigative journalist. Her acclaimed book Weapons of Math Destruction details how opaque, black-box algorithms rely on biased historical data to do everything from sentence defendants to hire workers. In 2017, O’Neil founded consulting firm ORCAA to audit algorithms for racial, gender and economic inequality.
Cathy O'Neil | Speaker | TED.com