Belief elicitation when more than money matters

Incentive compatible mechanisms for eliciting beliefs typically presume that money is the only argument in people?s utility functions. However, subjects may also have non- monetary objectives that confound the mechanisms. In particular, psychologists have argued that people favour bets where their ability is involved over equivalent random bets ?a so-called preference for control. We propose a new belief elicitation method that mitigates the control preference. With the help of this method, we determine that under the ostensibly incentive compatible matching probabilities method (Ducharme and Donnell (1973)), our subjects report beliefs 7% higher than their true beliefs in order to increase their control. Non-monetary objectives account for at least 27% of what would normally be measured as overcon?dence. Our paper also contributes to a re?ned understanding of control. We ?nd that control manifests itself only as a desire for betting on doing well; betting on doing badly is perceived as a negative.