Money vs Score: Evidences of payoff stakes in the dictator and ultimatum games

We designed dictator and ultimatum games, in which students shared not only money but also bonus points of a course in a university in Vietnam. Students attended experiments and were told that additional bonus points of a course were used as the endowment in the game. We find that dictators were generous in money games but remarkably more selfish in score games. However, dictators still expressed altruism and fairness in the score games. Students with a high score were more likely to share bonus points, especially for recipients with a lower score. In ultimatum games, responders were considerably more willing to accept a small number of offered points rather than a small amount of offered money. Behavior of the responder is not correlated with their score.