Abstract:  Several factors can account for the cooperative behaviors in social dilemmas, which include individual differences, reward and punishment system, task design and so on. People have a strong aversion to being the “sucker” in social dilemma situations so that those who prefer cooperation may be willing to punish free-riding. Researches demonstrated that although punishment could promote people’s cooperative behaviors temperately, their cooperation levels would drop down to the baseline when the punishment was removed. In previous studies, material punishment was adopted most frequently, however, social punishment has not been sufficiently investigated. Furthermore, there is no unanimous conclusion towards the issue whether the cooperation of the juveniles has any gender differences. So this study mainly examined the effects of moral punishment and interpersonal punishment on the junior middle school student’s cooperative behaviors. Last but not least, social value orientation is a relatively stable individual state and is defined as a tendency of allocation proportion between individual and others. Therefore, we further explored the relationship between social value orientation and student’s cooperative behaviors under different types of punishment. Accordingly, the present study consisted of 2 experiments. The first experiment was organized into a 3 × 2 factorial design. The first factor was the type of punishment, consisting of 3 levels: moral punishment, interpersonal punishment and no punishment. The second factor was the phase of punishment, consisting of 2 levels: punishment in the first phase and no punishment in the second one. Specifically, participants were randomly assigned to the three types of punishment. For punishment groups, participants were given the two phases of punishment. The second experiment was organized into a 3 × 2 × 2 factorial design. The first two factors were the same as experiment 1. The third factor was the type of social value orientation, encompassing 2 levels: prosocial participants and proself participants. The results are as follows, first, the cooperative level was significantly higher in the moral and interpersonal punishment conditions compared to no punishment condition, and the punishment effect remained when the interpersonal punishment removed. Second, punishment effects were significantly greater in the interpersonal and moral conditions than in the no punishment condition for the female participants, but the male participants just had this effect on the case of the interpersonal conditions. Third, a greater cooperative level observed in the moral and interpersonal punishment conditions across both prosocial participants and proself participants, but only the prosocial participants kept a higher cooperative level when the punishment removed. These results suggested that the moral and interpersonal punishment could promote the cooperative behaviors of the junior middle school students. In comparison, the interpersonal punishment had a more lasting effect, which was more prominent in the male group. Additionally, relative to the case of proself participants, there was a long-term effect on punishment for prosocial participants.

Key words:  moral punishment, interpersonal punishment, public goods dilemma, cooperation, social value orientation