Peter Backus at the University of Warwick, UK, calculated that he had a 1 in 285,000 chance of meeting the woman of his dreams in any given night in London. Not great odds: that’s 400 times fewer than the best estimates of how many extra-terrestrial life forms there are.

So how many people should you date before you decide to settle down? Fortunately there’s a formula to find this out, and it’s called Optimal Stopping Theory. The theory says if you reject all suitors for the first 37% of your dating time, then after that period you should pick the next person who surpasses all others you’ve seen before. This method has been seen in fish choosing suitors. It’s also supposed to work in other areas too, like hunting for houses. So now you know.

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