# The 37% Rule ...

• ..or How to Know When You've Found the Right Love Match for You.

Article By mathematician Lily Serna

Part of the love challenge is figuring out what you want in a partner and what characteristics are most important to you. With so many wonderful people out there, how do you know who the right person is? Everyone knows the agony of a bad date, so how do you know when to stop dating and commit to the most suitable person (if monogamy is your thing, that is)? The problem is that if you settle too early, you risk missing out on your ‘perfect match’, but if you wait too long, you risk that ‘perfect match’ finding another match and settling down themselves. In other words, you don’t want to commit to the first person who comes along, but you don’t want to wait too long either. So how many people should you date in order to find the optimal match? Well, it turns out maths has the answer.

There’s an area of mathematics called 'optimal stopping theory', that attempts to answer this general question: if you have a large choice of many things, how do you maximise your chance of choosing the best thing without having to know everything about every single choice? The problem is sometimes also called the secretary problem, the marriage problem and the sultan’s dowry problem, among others.

The first thing you should be aware of is the 37% rule. The idea behind this is that you should spend time observing before you start choosing; specifically, you should use the first 37% of your candidate pool (it could be your perfect house, a car, a new assistant) to establish a baseline, by which I mean get a sense of what’s out there. Put another way, the maths says you shouldn’t commit to anything/anyone in the first 37%. The next thing you need to know is the size of your candidate pool. Applied to the search for your life partner, this is tricky, because no one really knows how many possible matches we might have in our lifetime. But I reckon you can have a good crack at guessing.

Say you’d like to find a partner in the next 10 years, and you date approximately three people each year. That’s 30 people in total. Optimal stopping says that you should date the first 10 people (i.e. roughly 37%) without committing long-term. That means that for the next three years or so, just date and start to develop an idea of the person you’d like to commit to. This will be your baseline. After that, choose the first person who comes along who is a better match for you than all the ones you’ve dated before, and for the love of Pete (or whoever you chose), commit! That person has the highest probability of being the best match for you.

However, as with most things in probability, there are no guarantees, meaning there is a small chance that you will miss your perfect match in the first 37% of people you date, but if you follow this rule it will give you the best chance of finding your best match – and this is better than any other strategy out there.

There’s just one thing you need to know for the maths to hold up. You can’t go back to someone in that first 37% (which is just as well, because everyone knows what happens when you revisit exes). I think the 37% rule is a good rule of thumb and also one that in many ways people follow instinctively. It does support conventional wisdom that suggests you should date for a while before committing to someone to get a sense of your ideal partner. Without a dating history, you might not have enough knowledge about who’s out there to give yourself the best chance of finding the best partner for you.

Not convinced? Let’s do what most mathematicians do when faced with a tough problem: they look at a very simple scenario. Imagine Dani is trying to find her perfect match. There are only three people she could possibly date: Sam, Ben and Luke. Her criteria are that they should have similar values to her, and be ambitious and attractive. We know in advance (but she doesn’t) that Sam is a perfect match for her based on her criteria. We also know that Ben is a close second but unfortunately she’s not very compatible with Luke.

Now, there are six different scenarios with six different orders in which Dani could meet her suitors (in maths we call these permutations). According to the 37% rule, she has to reject the first 37%, and then she should commit to the first person she meets after that who is better than the first 37%. Of course, if you only have three people to choose from, 37% only amounts to one person. So she has to reject the first person, then choose the best person after that. Maths tells us that Dani will choose Sam, her perfect match, 50% of the time.

• @thecaptain
interesting but this article assumes that you meet three people who interest you enough to want to spend time with them.

• No you just apply it to any number of people you meet, even if it is only one. If it is only one, you should use them as a baseline and go on to meet other guys to compare.

• @thecaptain can this dating rule apply to the men you have dated overall in your life?

• @tuliplilly I think so. All the people from our past have helped us become clearer about what we want in a partner.

• @thecaptain I feel that I have learned from each relationship different lessons. I know that i was supposed to learn from my marriage. But I cant figure out the takeaway lesson. Maybe the pain is still there so i can't see past it. I know its important though and lessons can be applied. I know for sure how I don't want to be treated.