On reviewing the literature related to the game theory, it can be found that fairness plays an important role under the situation of a multi-person decision making. In this study, we developed a new version of three-person ultimatum game which was based on the sportsman-agent-advertiser triangle relationship in the real world to explore and verify the influence of the psychological feeling about fairness on the rate of rejection of the responder in the new ultimatum game. In experiment 1, participants were asked to play roles of sportsmen and confederates to play roles of agents who could propose a particular percentage of the endorsement fee as the rewarding commission from the sportsman to the agent. First, we found in experiment 1A that 30% was a critical threshold for the agent to feel fair and not to reject the proposal of commission. In experiment 1B, we deliberately manipulated the amount of commission to be much lower or higher than the threshold and verified the effect of unfairness on the rejection of the responder. In experiment 2, participants were asked to play roles of agents and confederates to play roles of sportsmen and advertisers in experiment 2A and 2B, respectively. The results of experiment 2A indicated that 30% was still the critical threshold during the negotiation of the commission from the sportsman to the agent. In experiment 2B, it was found that only the total amount of endorsement fee could influence the feeling of fairness and the following rejection of the agent while the amount of another commission from the advertiser to the agent did not matter. In addition to the development of a new version of three-person ultimatum game with a high ecological validity, this study also contributed to reveal the influence of fairness on the result of a multi-person decision making. However, more details about the rules of this new version of three-person ultimatum game and the more complicated interactive relationships between the three players in this game were both worthy of further studies.
