To determine whether subjects display social preferences in the field, we conduct a trading experiment with a pool of German Ebay users. Acting as a seller, we offer Amazon gift cards with values from 5 to 500 euros. Randomly arriving buyers, the subjects of our experiment, make take-it-or-leave-it price offers. From each offer we infer the fraction of the gains from trade that a buyer proposes to leave to the seller. We find that a large numbers of offers correspond to approximately equal sharing between the buyer and the seller. The amount of money at stake has no significant effect on the relative prices offered. More experienced buyers are more likely to display behavior consistent with the theoretical model.
