To compete for power and resources, people form groups including political parties, special interest groups, and international coalitions. We use economic experiments to investigate how people balance the desire for their group’s victory versus their own expenditure of effort. We design an economic tug of war in which the side that exerts greater costly effort wins a prize. In Experiment 1 , participants compete individually or in teams, which were assigned arbitrarily. In Experiment 2 , participants compete individually or in teams based on political partisanship, Democrats against Republicans. In both experiments, participants shirked by exerting 20% less effort in teams than in individual competition. Moreover, we did not find an effect of partisan framing: Participants exerted no more effort on political teams than arbitrary teams, contrary to theories asserting the automatic potency of partisanship. We discuss why it is difficult for groups, including political partisans, to mobilize in competition.

中文翻译：

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为团队拉力：政治党派之间的竞争

为了争夺权力和资源，人们组成了包括政党，特殊利益集团和国际联盟在内的团体。我们使用经济实验来研究人们如何平衡对团队胜利的渴望与自己的努力支出。我们设计了一种经济上的拔河比赛，在其中，付出更大努力的一方将赢得大奖。在实验1中，参与者可以单独竞争，也可以分组比赛。在实验2中，参与者根据民主党派与共和党的政治党派关系单独或小组竞争。在这两个实验中，参与者都比团队竞赛少了20％的努力而退缩。此外，我们没有发现党派框架的影响：参与者对政治团队的努力不比任意团队更多，与主张党派自动效力的理论相反。我们讨论了为什么包括政治游击队在内的团体很难动员起来参与竞争。