Question

I have the book Artificial Intelligence: A Modern Approach (by Stuart Rusell). I am reading chapter 16, “Making simple decisions”, but I do not get the main idea of the utility theory, can you provide a detailed example?

Answer 1

The main idea of utility theory is really simple: an agent’s preferences over possible outcomes can be captured by a function that maps these outcomes to a real number; the higher the number the more that agent likes that outcome. The function is called a utility function.

For example, we could say that my utility for owning various items is:

u(apple) = 10
u(orange) = 12
u(basketball) = 4
u(macbookpro) = 45

Economists (usually) consider humans as utility-maximizing agents. That is, we are always trying to maximize our internal utility function.

Once you have these numbers, then you can mix them in with probabilities and talk about expected utilities, optimal strategies, discounted future rewards, and many other fun things.

If you want to learn more, pick up a textbook on game theory, or read the first chapter of this agents book.