Rationality is a precise mathematical notion of what it means to do the right thing in any particular circumstance. It’s used in artificial intelligence because it provides a precise means to analyse and understand the properties of ideal behaviour we want to achieve, and a precise benchmark that we can measure the behaviour of systems we build.

Formally: a rational choice is a decision that increases the chance of achieving pre-defined goals. It’s measured by the outcome, not the process of computing a decision. A common approach is to measure the utility of the outcome of the decision/action. Rationality then is maximising the expected utility, .

jre420

  • perfect rationality
    • sometimes impossible! so bounded rationality might be forced. ex. choosing a university
  • bounded rationality
    • relies on limited information
    • relies on biases. trade-off is meant to maximise timeliness