Promises and cooperation: Evidence from a TV game show

We study the role of communication in a high stakes prisoner’s dilemma, using data from a television game show. 40 Percent of the players voluntarily promise to cooperate, and these players are 50 percentage points more likely to cooperate than players who do not volunteer a promise. However, promises that arise in response to an explicit question by the presenter of the show are uninformative about behavior. These results augment and qualify recent experimental findings on communication—people do not want to volunteer lies but may have no compunction in lying if they feel compelled to do so.