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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