90 percent of people are pessimistic, optimistic,
envious or trustful.
We have worked with 500 odd volunteers
attending a fair in Barcelona.
We have made them play social dilemmas,
where sometimes it's better to cooperate,
other times it's better to do the same as the others,
and we've been registering their actions
in different games against different people.
A group of nine researchers have been working on it.
We belong to Universitat Rovira i Virgili,
Universitat de Barcelona, Universidad de Zaragoza
and UC3M.
The aim was to see if everyone behaves
in their own way,
or if they can be grouped or classified somehow
depending on how they behave in different social situations.
The conclusion is very surprising:
nearly 90 percent of people can be classified
in four big groups.
The group of optimists,
who always behave thinking that the other part will behave
in a way that they both get as much as possible.
Pessimists, who try to minimise damage,
to guarantee themselves the best worst possible payment.
Then there are envious people,
who only want to get more than the others.
And finally there are good people,
who always tend to help the opponent.
Our algorithm doesn't know how to classify the remaining 10%,
and there might be subgroups that we can't identify.
It can also be people who play randomly,
because they don't want to think during the game.
These classifications may help to understand what happens
between two people, for example in a negotiation
or when they need to help each other.
They may have applications
to improve the simulation of human behaviour:
from simulating individual behaviour,
because you have types to assign the person you want to simulate,
to simulating the behaviour of large groups of people,
because you have an idea of what each fraction of those people does.
In collaboration with: