Overall, 72 subjects invest their endowment in four risky assets. Each combination 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 subjects...

We experimentally test overconfidence in investment decisions by offering participants the possibility to substitute their own for alternative investment choices. Overall, 149 subjects participated in two experiments, one with just one risky asset, the other with two risky assets. Overconfidence...