Thumbs Down for the Thumbs Up Emoji: Experimental Evidence on the Impact of Instantaneous Positive Reinforcement on Charitable Giving

Historically, positive reinforcement (PRI) for charitable giving happens after the fact; thank-you letters, calls, or gifts from the charities to donors. With online giving becoming more prominent, this creates an opportunity for instantaneous PRI. Our study offers the first evidence, to our knowledge, of the effect of instantaneous PRI on donation behavior. We conduct a large-scale online experiment on Amazon Mturk (n=2,375). Participants are randomly assigned to either a baseline with no PRI; a treatment in which subjects receive a static PRI thumbs up emoji (a general recognized gesture of approval); a treatment in which subjects receive a dynamic PRI thumbs up emoji [the emoji increases (decreases) in size as the size of the donation increases (decreases)]; and two other controls. We find that, consistent with much of the findings on thank-you letters, calls, and gifts, our instantaneous dynamic PRI has no significant positive effects on donation behavior. Surprisingly, we also find that static PRI results in significantly less being donated. These results suggest that organizations and policymakers should be hesitant in using instantaneous PRI, as it ranges from null to negative effects.