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NARRATOR: Like so many other[br]aspects of modern life,

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the search for a partner has gone online.

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People everywhere are[br]liking, swiping, winking,

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in the hopes of finding a match for life,

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or at least for the night.

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Dating apps take into account

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location, age, similar[br]interests listed in profiles.

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But the core of the mystique is,

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how do these apps figure out how desirable

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

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This is Algorithmics, the[br]space where we explore

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how invisible computer[br]controlled database sets of rules

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are making decisions for us every day.

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Let's start with OkCupid,

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which relies heavily on[br]a series of questions

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to see how well two people match up.

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OkCupid is pretty transparent

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about how they calculate[br]match percentages.

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They think of this equation[br]as the probability,

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two people will get along,

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and it's calculated based on questions

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both of you have chosen to answer.

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For each question, OkCupid asks[br]you to provide three things,

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your own answer, how you'd[br]like your match to answer

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and how important the question is to you,

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from irrelevant to very important.

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OkCupid assigns numerical[br]values to these ideas

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on a scale of zero to 250,

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and the algorithm assesses[br]how much your matches answers

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made you happy and vice versa.

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[gentle upbeat music]

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So if your matches answers[br]earned 250 out of 251

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possible points based on your preferences,

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that's 99.6% satisfactory.

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The same calculation is[br]done for your answers,

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compared to your matches preferences.

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Multiply these two satisfaction numbers,

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

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The more questions you answer,

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the more data the[br]algorithm has to work with,

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and the more confident it becomes

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in the matches it presents to you.

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Then there's Tinder, which prides itself

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on not requiring a 400[br]question registration process.

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But Tinder is much more[br]closed mouth than OkCupid

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about how it calculates matches.

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

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that each user has a[br]secret numerical rating,

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what the company internally[br]calls an Elo score.

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If a lot of people swipe right on you

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saying they like your profile[br]and want to match with you

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versus swiping left to[br]skip to the next person,

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your score will go up.

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Each swipe is like a vote.

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This person is more[br]desirable than that one.

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Tinder insists that this isn't[br]an attractiveness rating,

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desirability involves what you wrote

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in your profile for example.

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The company also says a lot of factors

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besides swiping affect your Elo score.

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A bit like love, the rest is a mystery.

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Every dating app works[br]slightly differently,

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but whichever you think gives you

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the best chance at finding love,

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this Valentine's Day,[br]remember that your ideal match

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might very well be the algorithm.

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[gentle upbeat music]

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