Rand David G, Pfeiffer Thomas, Dreber Anna, Sheketoff Rachel W, Wernerfelt Nils C, Benkler Yochai
Program for Evolutionary Dynamics, Harvard University, Cambridge, MA 02138, USA.
Proc Natl Acad Sci U S A. 2009 Apr 14;106(15):6187-91. doi: 10.1073/pnas.0811552106. Epub 2009 Mar 30.
People often favor members of their own group, while discriminating against members of other groups. Such in-group favoritism has been shown to play an important role in human cooperation. However, in the face of changing conflicts and shifting alliances, it is essential for group identities to be flexible. Using the dictator game from behavioral economics, we demonstrate the remodeling of group identities among supporters of Democratic presidential candidates Barack Obama and Hillary Clinton. After Clinton's concession in June 2008, Democrats were more generous toward supporters of their own preferred candidate than to supporters of the other Democratic candidate. The bias observed in June persisted into August, and disappeared only in early September after the Democratic National Convention. We also observe a strong gender effect, with bias both appearing and subsiding among men only. This experimental study illustrates a dynamic change in bias, tracking the realignment of real world conflict lines and public efforts to reconstitute group identity. The change in salient group identity we describe here likely contributed to the victory of Barack Obama in the 2008 presidential election.
人们往往偏袒自己群体的成员，同时歧视其他群体的成员。这种内群体偏袒已被证明在人类合作中发挥着重要作用。然而，面对不断变化的冲突和联盟的转变，群体身份的灵活性至关重要。我们运用行为经济学中的独裁者博弈，展示了民主党总统候选人巴拉克·奥巴马和希拉里·克林顿的支持者之间群体身份的重塑。2008年6月克林顿让步后，民主党人对自己偏好候选人的支持者比对另一位民主党候选人的支持者更慷慨。6月观察到的这种偏见持续到了8月，直到民主党全国代表大会后9月初才消失。我们还观察到了强烈的性别效应，即这种偏见仅在男性中出现和消退。这项实验研究说明了偏见的动态变化，追踪了现实世界冲突线的重新调整以及公众重建群体身份的努力。我们在此描述的显著群体身份的变化可能促成了巴拉克·奥巴马在2008年总统选举中的胜利。
