Giving it now or later: altruism and discounting

We experimentally study the e¤ect of time on altruism. By postponing payments in a standard Dictator game, subjects allocate a future payment between themselves and others. Since both the payoffs of the Dictator and the Receiver are delayed until the same time, standard intertemporal utility maximization would predict that waiting time should not affect the Dictator's choice. In this respect, we observe that Dictators' decisions are not affected, as long as the time interval between the decision and payment is not large. On the other hand, for large time gaps, subjectsbecome more self-interested.