NARRATOR: Like so many other
aspects of modern life,

the search for a partner has gone online.

People everywhere are
liking, swiping, winking,

in the hopes of finding a match for life,

or at least for the night.

Dating apps take into account

location, age, similar
interests listed in profiles.

But the core of the mystique is,

how do these apps figure out how desirable

you personally might be to a
potential match and vice versa?

This is Algorithmics, the
space where we explore

how invisible computer
controlled database sets of rules

are making decisions for us every day.

Let's start with OkCupid,

which relies heavily on
a series of questions

to see how well two people match up.

OkCupid is pretty transparent

about how they calculate
match percentages.

They think of this equation
as the probability,

two people will get along,

and it's calculated based on questions

both of you have chosen to answer.

For each question, OkCupid asks
you to provide three things,

your own answer, how you'd
like your match to answer

and how important the question is to you,

from irrelevant to very important.

OkCupid assigns numerical
values to these ideas

on a scale of zero to 250,

and the algorithm assesses
how much your matches answers

made you happy and vice versa.

[gentle upbeat music]

So if your matches answers
earned 250 out of 251

possible points based on your preferences,

that's 99.6% satisfactory.

The same calculation is
done for your answers,

compared to your matches preferences.

Multiply these two satisfaction numbers,

take the square root and
that's your match percentage.

The more questions you answer,

the more data the
algorithm has to work with,

and the more confident it becomes

in the matches it presents to you.

Then there's Tinder, which prides itself

on not requiring a 400
question registration process.

But Tinder is much more
closed mouth than OkCupid

about how it calculates matches.

Tinder's co-founder did
reveal to a fast company

that each user has a
secret numerical rating,

what the company internally
calls an Elo score.

If a lot of people swipe right on you

saying they like your profile
and want to match with you

versus swiping left to
skip to the next person,

your score will go up.

Each swipe is like a vote.

This person is more
desirable than that one.

Tinder insists that this isn't
an attractiveness rating,

desirability involves what you wrote

in your profile for example.

The company also says a lot of factors

besides swiping affect your Elo score.

A bit like love, the rest is a mystery.

Every dating app works
slightly differently,

but whichever you think gives you

the best chance at finding love,

this Valentine's Day,
remember that your ideal match

might very well be the algorithm.

[gentle upbeat music]

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