Today i want to talk to you
about the mathematics of love.
I think we can all agree
that mathematicians
are famously excellent
at finding love.
But it's not just because
of our dashing personalities
our superior conversational skills
or our excellent pencil cases,
it's also because we've done
a lot of work into the maths
of how to find the perfect partner.
in my favorite paper on the subject
which is entitled,
"Why I Don't Have a Girlfriend."
peter backus tries to rate
his chances at finding love
now, peter is not a very greedy man
of all of the available women in the UK
all that peter's looking for is
somebody who lives near him,
somebody in the right age range,
somebody with a university degree,
somebody he's likely to get on well with
somebody attractive
somebody who is likely to find him attractive
(laughter)
and comes up with an estimate of 26 women
in the whole of the UK
it's not looking very good, is it peter?
now just to put that into perspective
that's about 400 times fewer
than the best estimates
of how many intelligent
extra-terrestrial life forms there are
and it also gives peter a
1 in 285,000 of bumping
into any one of these special ladies
on a night out
I'd like to think that's why
mathematicians don't really bother
going on nights out anymore
The thing is is that i personally
don't subscribe to such a pessimistic view
i know, just as well as you do,
that love doesn't really work like that
human emotion isn't neatly ordered
rational or easily predictable
but i also know that that doesn't mean
that mathematics
doesn't have something it can offer us
because, love, as with most of life
is full of patterns
and mathematics is ultimately
all about the study of patterns
pattersn from predicting the weather
to the fluctuations of the stock market
to the movement of the planets
or the growth of cities
if we're being honest, none
of those things are neatly ordered
or easily predictable either
because i believe that mathematics
is so powerful that is has the potential
to offer us a new way of looking
at almost anything
even something as mysterious as love
and so, to try to persuade you
of how totally, excellent,
and relevant mathematics is
I want to give you my top three
mathematically verifiable tips for love
okay, so, top tip #1
how to win at online dating
so my favorite online dating website
is OkayCupid
not least because it was
started by a group of mathematicians
now because they're mathematicians
they have been collecting
data on everyone whose been using
their site for almost a decade
and they've been trying to search
for patterns in the way that we
talk about ourselves
and the way that we interact with each other
on online dating websites
and they've come up with
seriously interesting findings
but my particular favorite
is that it turns out
that one an online dating website,
how attractive you are
does not dictate how popular you are
and actually having people
think that you're ugly can
work to your advantage
let me show you how this works
okay, in a thankfully voluntary section
you are allowed to rate how attractive people are
between 1 and 5
and if we compare this score
this average score
to how many messages a selection
of people receive
you can begin to get a sense
of how attractiveness
links to popularity on online dating
so this is a graph that the online
okay cupid guys have come up with
and the important thing
to notice is that it's not totally true
that the more attractive you are
the more messages you get
but the question arises then
of what is it about people up here
who are so much more popular
than people down here?
even though they have the
same score of attractiveness
and the reason why is that
it's not just straight forward looks
that are important
so, let me try to illustrate their findings
with an example
if you take someone like porcia di rossi
everybody agrees that porcia di rossi
is a very beautiful woman
nobody thinks that she's ugly
but she's not a supermodel
if you compare porcia di rossi
to someone like sarah jessica parker
now, a lot of people
myself included
think that sarah jessica parker
is seriously fabulous
and possibly one of
the most beautiful creatures to have evr
walked the face of the earth
but, some other people
e.i., most of the internet
seem to think that she looks a bit like a horse
(laughter)
now, i think that if you ask people
how attractive sarah jessica parker
or porcia di rossi are
and you ask them to give them a score between one and five
i reckon that they would average out to the same score
but the way that people would vote
would be dry different
so porcia's scores would all be clustered around
the four because everybody agrees that she's
very beautiful
whereas sarah jessica parker divides opinion
there a huge spread in her scores
and actually it's this spread that counts
it's this spread that makes you more popular
on online internet dating websites
so what this means then
is that if some people think that
you're attractive
you're actually better off
having some other people
think that you're a massive minger
that's much better than everybody
thinking that you're the cute girl next door
i think that this makes a bit more sense
when you think in terms of the people
who are sending these messages
so let's say that you think somebody's attractive
but you suspect that other people
won't necessarily be that interested
that means that there is less competition for you
and that there's an extra incentive
for you to get in touch
whereas compare that to if you think
somebody is attractive but
you suspect that everybody is going
to think they're attractive
well, why would you bother humiliating yourself
here's where the really interesting part comes
people choose the pictures
that they use on an online, dating website
they often try to minimize the things
that they think people will find unattractive
the classic example is that
people who are a little but overweight
deliberately choosing a very cropped phto
or bald men for example
deliberatly choosing pictures
where they're wearing hats
but this is the opposite of
what you should do if
want to be succesful
you should really instead
play up to whatever it is that makes you different
even if you think that
some people will find you unattractive
because the people who fancy you
are just going to fancy you anyway
and the unimportant losers who don't
well, they only play out to you r advantage
Okay, top tip #2, how to pick
the perfect partner