Do you believe in true love? As in, there is one person out there that
you are meant to be with? Some people do. Then, there are the rest of us
who hold a more pluralistic view: there is a pool of people out there that
for all intents and purposes, will make us pretty happy. Of course, these
two views aren’t necessarily at odds with one another. For instance,
within any pool there might still be an ordering. Technically, we can
call the person who ranks the highest our true love. Although in our
case, the second and third place is basically almost as good. Whereas if
you believe in one true love, then the drop off is much sharper.

The true love advocates believe that the size of everyone’s pool is
exactly 1. If you subscribe to this belief, then the rest of this post is
irrelevant. But if you think there are more than one person in your pool,
then the question is just how many people are in there? Are there
hundreds, thousands, or tens of thousands of potential true loves? The
actual number is relevant here, because all else being equal, the
probability of finding a person you love is directly proportional to the
size of your pool.

One way to estimate this number is to ask yourself roughly one out of how
many people do you consider to be true love material. Is it one in a
hundred? A thousand? Five thousand? Ten thousand? I know this feels
rather abstract. One way to ground these numbers is to think back to your
high school. Roughly how many people would you date from your high
school? How many out of that number would you guess would have turned out
pretty well? Then, divide that number by the number of people in your
high school. As I write this I’m realizing that it may not be a good
measure. If you didn’t particularly enjoy your high school years
(speaking from personal experience here), your numbers are likely to be
skewed. Well, all I ask is that you make a stab at it.

Once you have settled on a ratio, the number will fall out. Starting from
300,000,000, the population of the U.S., roughly 2/3 of the population are
adults over the age of eighteen, according to the census. Which leaves us
200,000,000. Then out of this number, roughly 2/3 are married. That
leaves us 66,000,000 single adults to work with. Assuming that you are
only interested in one of the two genders, cut that number by half which
leaves us 33,000,000. Finally, say if you believe that 1 out of 1,000 people
qualifies as true love material, that means your pool has 33,000 people in
it in the entire U.S.. To make that number a little more concrete, say
you live in Boston, a city with population of 600,000. Then roughly 66
people in your pool would reside in the same city. Of course, we have
made many wild assumptions in this calculation, including that the
concentration of your true love is the same in Boston as it is in Lyndon,
Kansas (no offense Liana ).

Another way to make some rough estimates would be to start from the
qualities you care about and ask yourself what percentage of the
population exhibit those qualities. Say you care about honesty, maybe you
think 1 out of 10 people is honest. Say you care about attractiveness,
maybe you deem 20% of all people attractive. Now, what other
characteristics are absolute musts for you? Sense of Humor? Height?
Success? Income? Intelligence? Sense of adventure? Reliability?

Let’s just assume that there are 10 characteristics that you absolutely
care about and that you want the top 50% in each of them. Now, what’s the
probability that a random person will meet all your 10 characteristics?
That would be 1/2 x 1/2 x … x 1/2, or 1/2 to the tenth power, which is
1/1024, or roughly one in a thousand. If on the other hand, there turn
out to be 20 characteristics that you care about, that would yields 1 in
1,048,576. If indeed one in a million meets your criteria then that means
there are only 33 people out of the entire U.S. in your pool! The city of
Boston is too small to contain even one single person. These figures tend
to suggest that we shouldn’t be too picky. Since, each factor you care
about can cut your pool by half. Plus, we are only talking about twenty factors
here. For many people, attractiveness alone can easily occupy ten of the
twenty factors (facial features, body proportion, amount of chest hair, etc.
Shall I remind you the man-hands episode from Seinfeld?).

The good news is that things aren’t quite as bad because previously, we
had assumed that all characteristics are mutually independent. Which is
not true in reality. Indeed, researchers have shown for example that a person’s
height is linked to success. Apparently, a disproportionally high
percentage of CEOs are tall. So if you like tall and successful people,
then your pool might be bigger than if you had picked two completely
independent characteristics. But things can also work the other way. If
you want someone who’s laid back and intense, if you want an adventurous
joker who’s also dependable, or if you want a highly successful person who
won’t make you move when she gets a better job offer at east-bum-f*ck,
then the pool might shrink faster. Since, the personality traits that
give rise to these divergent characteristics are often at odds with one
another and hard to come by in the same person.

Having a better picture of how these characteristics are interrelated will yield more accurate estimates. It would be interesting to construct a probabilistic model for the set of common characteristics. Perhaps the joint distribution can be represented as a Bayesian network. We can use data from social science and psychology to determine the independence relationships between some of the characteristics. Once constructed, this model can be used as the basis for a true love calculator. You select your location (e.g. Boston), the characteristics you care about (e.g. honesty, shoe size, cleanliness) and specify how strictly each criterion is to be measured (e.g. 10% or 20% of the population), hit “enter”, then out pops the number of true loves who live in your city (if it can give you their names and addresses, then we are talking…).

Can you think of other ways to estimate the size of a given person’s true love pool?