Seth Sanders (Duke University)
Abstract. This paper presents a novel experiment on identity and individual social preferences. Using a within subject design and new empirical methods, we find more than twenty percent of subjects destroy total income – at personal cost – to earn more than subjects outside their group. Minimal groups divide subjects according to arbitrary criteria, and political groups divide subjects according to party affiliations and opinions. In both treatments, political partisans behave more selfishly and destructively towards out-group members. Political Independents do so only in political groups, though less strongly. Thus group divisions are salient for some people but not others, depending on individual differences and identities. We also show a strong pattern that when making choices between group members, choices that leave subjects close to indifferent take significantly more time to make than choices where subjects have a strong preference. In addition, subjects who take into account the social context of decision making take significantly more time to make choices than subjects who ignore social circumstances.