| Objectives: In order to provide better public goods,it is common to set long-term collective goals based on project requirements.However,it is currently unclear whether setting long-term collective goals is beneficial for improving and maintaining cooperation.Therefore,this study aims to explore the impact of setting collective goals and the difficulty of goals on cooperation in public goods game,as well as the impact of setting intermediate goals or punishments on achieving the ultimate goal and maintaining cooperation.Methods: This study consisted of three experiments,using the public goods game with collective contribution goals.Experiment 1 examined the role of collective contribution goals,with 120 college students randomly assigned to a baseline group(no goal,40 participants),a medium contribution goal group(40 participants),and a high contribution goal group(40 participants).By comparing the contribution behavior of the three groups of participants in repeated public goods game,the effects of collective contribution goals on the level of cooperation were investigated.Experiments 2 and 3explored the achievement of the ultimate goal and changes in the level of cooperation under intermediate goal and centralized punishment,respectively,based on Experiment1.Experiment 2 has 40 college students participating in a public goods game under intermediate goal.Experiment 3 has 40 college students participating in a public goods game under centralized punishment.Results: Experiment 1 found that(1)setting a 50% or 75% contribution goal could increase the level of contribution;(2)compared with the 50% goal condition,the contribution level under the 75% goal condition was higher but the goal achievement rate was lower;and(3)goal commitment has moderating effect on the relationship between goal difficulty and the level of cooperation.Experiment 2 found that(4)intermediate goals could not improve the achievement rate of the ultimate goal or increase the level of cooperation;and(5)compared with the group successfully achieving midterm goals,failing to meet intermediate goals would lead to lower contribution.Experiment 3 found that(6)adding centralized punishment could increase the achievement rate of the ultimate goal,but could not increase the level of cooperation.The punishment group increased contribution in the early stage but decreased contribution when approaching the goal in the later stage.(7)In the early stage of the game,goal commitment plays a complete mediating role between punishment and the level of cooperation.Conclusions: In situations where collective interests conflict with individual interests,(1)setting clear collective goals promotes cooperation more than having no goals.(2)Within a certain range,challenging goals promote cooperation more effectively.(3)Goal commitment is both the key to different effects of goals with varying levels of difficulty and to the success or failure of goals at the same level of difficulty.(4)Only setting intermediate goals does not help improve cooperation,and not achieving intermediate goals can even further worsen cooperation.(5)Centralized punishments can improve the achievement rate of goals and also improve cooperation in the initial stage.Goal commitment has the mediating effect in the initial stage.However,compared to long-term cooperation,people are more concerned about whether the goals have been achieved;thus,cooperation will still deteriorate in the later stage. |
