How do peers influence the impact of incentives? Despite much work on incentives, little is known about the spillover effects of incentives. We investigate two mechanisms by which these effects can occur: through peers' actions and peers' incentives. In a field experiment on snack choice (grapes...

Little is known about how peers influence the impact of incentives. We investigate two mechanisms by which these effects can occur: through peers' actions and peers' incentives. In a field experiment on snack choice in the school lunchroom (choice of grapes versus cookies), we randomize who...