In the dictator game, the recipient's opportunity to send a message to the dictator increases giving. This paperreports two experimentswhich study how the timing of messages affects dictators' decisions (experiment 1) and which value recipients attach to communication opportunities (experiment...

Altruists and envious people who meet in contests are symbionts. They do better than a population of narrowly rational individuals. If there are only altruists and envious individuals, a particular mixture of altruists and envious individuals is evolutionarily stable.

In the dictator game, the recipient's opportunity to send a message to the dictator increases giving. This paperreports two experimentswhich study how the timing of messages affects dictators' decisions (experiment 1) and which value recipients attach to communication opportunities (experiment...

We introduce the give-or-destroy game that allows us to fully elicit an individual s social preference schedule. We find that about one third of the population exhibits both pro-social and anti-social preferences that are independent of payoff comparisons with those who are affected. We call...