Extraversion and risk preference in portfolio theory.

One hundred seventy-eight male and female undergraduates completed the Eysenck Personality Inventory and indicated their risk preference assessed under the assumptions of Coombs' portfolio theory. Extraverts preferred higher risk significantly more than did introverts, and also showed significantly greater risk preference change as expected value increased. It was suggested that a theoretically defensible selection of both personality variables and a risk assessment model may lead to greater personality-risk predictability.