Two participants have to decide jointly, with the discussions preceding their choice being video/audiotaped. For two tasks, one with and one without strategic interaction, we refer to obvious reasoning styles as mental models. The videotaped discussions are analyzed according to which mental...

Overall, 72 subjects invest their endowment in four risky assets. Each com-bination of assets yields the same expected return and variance of returns. Illusion of expertise prevails when one prefers nevertheless the self-selected portfolio. After being randomly assigned to groups of four...