Decision Making: Is It All 'Me, Me, Me'?

Psychologists carried out the first systematic tests of team reasoning theories by assessing two well known views of how people behave. Orthodox or classical game predicts that people will act for selfish reasons. Team reasoning theory suggests individual self-interest is not always foremost in the way people act as they will act in the best interest of their "team."

Lead researcher Professor Andrew Colman, of the University of Leicester School of Psychology, said: "We have shown that, in some circumstances, decision makers cooperate in their collective interests rather than following the purely selfish predictions of orthodox game theory.

"We carried out two experiments designed to test classical game theory against theories of team reasoning developed in the 1990s by British game theorists. According to classical game theory, decision makers invariably act in their individual self-interest, leading to "Nash equilibrium", named after the US game theorist and Nobel laureate John Nash, depicted in the biopic A Beautiful Mind.

"Theories of team reasoning were developed to explain why, in some circumstances, people seem to act not in their individual self-interest but in the interest of their families, companies, departments, or the religious, ethnic, or national groups with which they identify themselves."

Professor Colman is delighted with the results. He said: "Team reasoning is a familiar process, but it is inexplicable within the framework of orthodox game theory. Our findings show for the first time that it predicts decision making more powerfully than orthodox game theory in some games."

The study was carried out by Professor Andrew Colman and Dr Briony Pulford at the University of Leicester in collaboration with Dr Jo Rose of the University of Exeter.

The results will be published within the next few months in the journal Acta Psychologica, together with commentaries from decision theorists from the UK, the Netherlands, and the US.