Decoding Love - Andrew Trees [63]
But back to the lucky number twelve. How in the world can we possibly arrive at such a precise number? To understand that, I’m going to ask you to play a game. Mathematicians have called this game by a variety of names. We are going to play the version known as the dowry problem. Let me set the scene. You are the king’s most trusted adviser. He wants to find you a lovely bride (or groom), but he also wants to make sure that you truly are as wise as he thinks you are. So, he arranges a challenge for you. He sends out his minions and finds one hundred of the most beautiful women in the land. He then provides each of them with a dowry, only he doesn’t provide them with the same dowry. Each woman has a dowry different in value from all the other women. Your challenge is to pick the woman with the highest dowry. If you succeed, the beautiful bride and the sumptuous dowry are yours to enjoy, and your place at the king’s side is secure. If you fail, he’s going to chop your head off. Oh, and one more thing, you meet the women one at a time, and once you have dismissed a woman, you can never call her back. Ready? Let’s play.
Being the brilliant adviser that you are, you probably have already figured out the math for all of this. I, of course, am terrible at math and am relying entirely on the excellent article by Peter F. Todd and Geoffrey F. Miller called “From Pride and Prejudice to Persuasion: Satisficing in Mate Search,” which can be found in Simple Heuristics That Make Us Smart. Once you crunch the numbers, you realize that your best chance is to pass on the first thirty-seven women and then pick the next woman who has a higher dowry than any of the women who came before her. Mathematicians have dubbed this rather obviously the “37 percent rule.” By seeing the first thirty-seven women, you will give yourself a 37 percent chance of choosing the highest dowry. Not the greatest of odds when you are under the threat of having your head chopped off but a better percentage than you will get with any other number. If the king lets you play the field a little bit, you can improve your chances dramatically. If you can keep one woman while you continue your search, you can increase your odds of finding the best dowry to 60 percent. Not too shabby.
Those of you who feel a little letdown about the 37 percent rule, raise your hands. Thirty-seven is nowhere near the twelve I promised. Dating thirty-seven people sounds exhausting. Well, apparently Todd and Miller agreed with you, and they set about tweaking the game in various ways to see if they could find a better way.
Instead of the 37 percent rule, you could try the “Take the next best” strategy. Of course, you are going to have to give up on the idea of “the one.” If your sole criteria is trying to find the single-best mate, you’ve got to stick with the 37 percent rule. But if you are willing to accept anyone in the top 10 percent, you can follow the 14 percent rule. This rule works as you might expect. You pass on the first fourteen women (or men) and then choose the next woman who is better than those first fourteen. If you do this, you have an 83 percent chance of ending up with someone in the top 10 percent. If you are willing to accept anyone in the top 25 percent, you only need to look at the first seven women and then choose to have a 92 percent chance of success. Let’s say you are unlucky in love and just want to avoid marrying someone in the bottom 25 percent. Then you only need to check out three women, and you will have less than a 1 percent chance of ending up with a loser. That may not sound all that great, but the 3 percent strategy still does a better job of avoiding losers than the