Sharing responsibility for the good

Relative to individual decision-making, decision-makers in markets have been argued to be more willing to accept negative externalities of their actions. A key mechanism potentially explaining this phenomenon is a diffusion of responsibility between actors in markets. In the preregistered experiment reported here, we test for an effect of responsibility diffusion in a new context: economic transactions with positive externalities. In particular, we test if participants’ willingness to pay for the vaccination of a child against measles differs between individual and bilateral decision-making. We find no such effect. Our study thus adds an(other) instructive null-result to the literature trying to pin down precisely which aspects of market interactions affect precisely which types of morally relevant decisions.