Hello folks, in this unit we're going to

look at two extremely simple models of a

rather complex phenomenon;

that is, the phenomenon of cooperation in

social systems. How is it that intrinsically

selfish individuals living in a society, or

any kind of social group, learn or find a way

to cooperate in order to increase the

benefit for all members of the group?

That's what these models are about.

We're going to look at two of the most

famous of such models, the Prisoner's

Dilemma model and the so-called

El-Farol Model. Let's get started.

The existence of cooperation is often a

mystery, in biology and in the social sciences.

The main assumption of natural selection,

and much of social and economic theory is

that individuals act in order to maximize

their own so-called "utility" which might

mean: their reproductive success, their profit,

their happiness, or what have you. In

short, individuals are assumed to be selfish

and yet the phenomenon of cooperation and

even altruism are evident at all levels of biology

and in society. How does this come about? So

this leads to some questions. How is it that

cooperation comes about in biological

populations? In communities? In societies

of selfish individuals? And how does it

persist? And finally, how can we create

conditions to make it happen? It's very

difficult to design experiments to explore

these questions. So, people have, especially

in the field of complex systems, largely looked

at these kinds of questions through the

use of simplified computer models which

often are called "idea models". An idea

model is an idealized model of a phenomenon

that shows that a proposed mechanism might

be plausible, or two explore general

mechanisms that underlie behavior, explore

the effects of different kinds of environments,

different kinds of parameters on the

behavior, et cetera. In this unit, we're

going to take a quick tour of two classic

idea models in this area. First, the Prisoner's

Dilemma model, which has been explored

in great detail by political scientist

Robert Axelrod and the so-called El-Farol

problem which was devised by economist

Brian Arthur. Really, this is just going to

scratch the surface of idea models

addressing questions about cooperation in social

systems. But hopefully, this will give you a flavor

of the kinds of things that people have done

in the past and I've put a number of

references up on our course materials

page to get you started with some reading

with some reading about things that have

been going on more recently in this area.