Alpízar, Francisco and Peter Martinsson. 2010. “Don’t Tell Me What to Do, Tell Me Who to Follow! Field Experiment Evidence on Voluntary Donations.” EfD Discussion Paper 10.
The authors conducted a field experiment in a protected area to explore the effects of conformity to a social reference versus a comparable, but imposed, suggested donation. By keeping the intrinsic valuation of the good constant, they were able to explore the effect of these two treatments on self image.
Treatment 1 (conformity to a social reference), saw a significant increase in people donating and an increase in the average conditional and sample donations as the reference increased. They also observed an inflection point, where the share of donations and the conditional donation were reduced as the reference increased beyond a certain level. Treatment 2 (donation amount suggested) showed more people donating, but had lower conditional donations. They concluded that people use their peers as a reference to conform to, but partially reject an imposed suggestion on how to behave.