The authors model the role of personality traits in explaining the disposition effect building on realization utility theory and Big 5 model and moving from an aggregate level to interindividual differences. The experimental analysis, combining NEO Revised Personality Inventory measures with individual financial data from a trading simulation run by 230 individuals in China and Italy, shows that the disposition effect is driven by 2 distinct psychological processes, one related to holding losers and the other to selling winners. These 2 behavioral mechanisms are uncorrelated and influenced by different personality traits. Controlling for different demographic variables, the authors show (a) a greater sensitivity of the rewarding system that...