Background: The aim of this study was to determine whether people respond differently to low and high stakes in Dictator and Ultimatum Games. We assumed that if we raised the stakes high enough, we would observe more self-orientated behavior because fairness would become too costly, in spite of a possible risk of a higher punishment.
Methods: A questionnaire was completed by a sample of 524 university students of biology. A mixed linear model was used to test the relation between the amount at stake (CZK 20, 200, 2,000, 20,000 and 200,000, i.e., approximately $1-$10,000) and the shares, as well as the subjects' gender and the design of the study (single vs. multiple games for different amounts).
Results: We have discovered a significant relationship between the amount at stake and the minimum acceptable offer in the Ultimatum Game and the proposed shares in both Ultimatum and Dictator Games (p = 0.001, p<0.001, p = 0.0034). The difference between playing a single game or more games with several amounts at stake did not influence the relation between the stakes and the offered and minimum acceptable shares.
Women proved significantly more generous than men in their offers in the Dictator Game (p = 0.007). Conclusion: Our results suggest that people's behavior in the Dictator and Ultimatum Games depends on the amount at stake.
The players tended to lower their relative proposed shares, as well as their relative minimum acceptable offers. We propose that the Responders' sense of equity and fair play depends on the stakes because of the costs of maintaining fairness.
However, our results also suggest that the price of fairness is very high and that it is very difficult, probably even impossible, to buy the transition of Homo sociologicus into Homo economicus.