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  • I think we can all agree that mathematicians are well known for being extremely popular

  • with the opposite sex. But it's not just because of our dashing personalities and superior

  • pencil cases. Oh no. It's also because we've have done an awful lot of work in the mathematics

  • of, how to find the perfect partner. In my favourite paper on the subject, entitled

  • "Why I don't have a girlfriend", Peter Backus tries to work out his chances of finding love.

  • In particular, he is looking for single women who live near him in the UK, are of the right

  • age range, have an university degree, are likely to be attractive, and he is likely

  • to get in well with. And the total he comes up with is 26 in the whole of the UK.

  • Now to just put that in perspective that's 400 times fewer than the best estimates of

  • how many intelligent extra-terrestrial life forms there are. And it gives him a 1 in 285,000

  • chance of meeting one of these 26 ladies on a given night out. It's not looking very good

  • is it Peter? Now I don't prescribe to this frankly pessimistic

  • view. I think there is a lot of people you can have a successful relationship with if

  • you want to. But given all the people you'll date throughout your life time, how do you

  • know when is the right time to settle down? Of course it isn't wise to cash in the first

  • person who shows you any interest, but equally if you want to be truly happy you can't leave

  • it too long. As my good friend Jane Austin says "An unmarried woman of seven and twenty

  • can never hope to feel or inspire affection again." Yeah, thanks a lot Jane, what do you

  • know about love? But the thing about dating is that once you've

  • made up your mind, you can't go back and change it. Typically people aren't that happy being

  • recalled later after being passed up for somebody else. So many people should you date before

  • you decide to settle down? Now, if only there were some kind of a mathematical

  • formula for a dating strategy that we could use to help us. Oh wait, there totally is!

  • And its called optimal stopping theory. So, let's say you start dating at about 15

  • years old and ideally you'd like to settle down at 35. And the rules are you can't see

  • ahead of what you could've had once you settle down and you can't go back and change your

  • mind. So the theory says that in the first 37% (or 1 over e) of your dating time, you

  • should reject everybody as serious marriage material. And after that period has passed

  • you should pick the next person that comes along that is better than everybody else you've

  • seen before. And if you do that it can be mathematically proven that you're maximising

  • your chances of picking the perfect partner. So this method has been observed in the wild.

  • So certain types of fish will reject any suitor who comes along within the first 37% of the

  • mating season and then pick the next male fish that comes along that's bigger and burlier

  • than all of the rest. But you could also use this strategy when

  • you're looking to buy or rent a house. Say you got three months in which to look for

  • a house. You should spend the first month (30% of the time window) just getting a feel

  • for the market, going to see houses but never cashing in on any of them. And after that

  • period has passed you then pick the first house that comes along that is better than

  • everything else you've seen before. Now this method does come with risks, it doesn't

  • guarantee that you'll get the perfect partner, it just gives you your best chance of finding

  • them. You could, for instance, be really unlucky and have your perfect match appear within

  • that first 37% window when you're rejecting everybody. And if that's the case, unfortunately

  • the maths says that you'll grow old alone probably be surrounded by cats.

  • Or let's say you got really unlucky and the first 37% of the people you dated were just

  • incredibly dull and boring and terrible people. And that's ok because you're still rejecting

  • all of those people. But let's say the next person that comes along is still really dull

  • and boring but marginally less terrible everybody you'd seen before. If you're following the

  • maths and marry that person you'd just be in a relationship that was suboptimal. Sorry

  • about that. But if everybody followed this strategy then

  • one in three people who do, they can settle down in the knowledge that maths says they'd

  • done the very best they can.

I think we can all agree that mathematicians are well known for being extremely popular

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A2 settle dating partner perfect strategy rejecting

How to find your perfect partner! I Number Hub with Hannah Fry I Head Squeeze

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    Halu Hsieh posted on 2014/05/10
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