Different carrots and different sticks: do we reward and punish differently than we approve and disapprove?

This paper reports lab data from four games in order to analyze and compare the motivations behind monetary punishment and reward and their non-monetary counterparts, disapproval and approval, an important question given that both types of punishment/rewards affect cooperation and norm compliance. The results in our games support the hypothesis that a motivation akin to reciprocity plays the key role for approval and disapproval whereas payoff comparisons play the key role for monetary rewards and punishment.