Bank and Response: A Field Experiment on Peer Information and Water Use Behavior

Perception of social rank, or how we perform relative to our peers, can be a powerful motivator. While research exists on the eect of social information on decision making, there is less work on how ranked comparisons with our peers inuence our behavior. This paper outlines a eld experiment conducted with 5,180 households in Castro Valley, California, which used household mailers with various forms of peer information and social rank messaging to motivate water conservation. The experiment tests the eect of a visible social rank on water use, and how the cooperative and competitive framing of rank information inuences behavioral response. Dierence-in-dierence and matching methods reveal sizable treatment eects of the mailers on household water use (reductions of 13-17 gallons per day, depending on mailer version). However, households with relatively low or high water use in the pre-treatment period responded dierently to information framing. We nd that neutrally-framed rank information caused a boomerang eect (i.e., an increase in average water use) for low water use households, but this eect was eliminated by competitive framing. At the same time, competitively-framed rank information demotivated high water use households, increasing their average water use further. This result is supported by evidence that the competitive frame on rank information increased water use for households who ranked last in the peer group - a detrimental last place eect from competitive framing.