Feinberg et al. pc excluding one of the prospective group members.We hypothesized that when participants could relate reputa- matize do not cont tional information anc recipients could act on the infor d the link between sip and cooperation,finding that g ation can facilitate indirect reciprocity(Sommerfeld,Krambeck Semmann,Mi inski,2007)and deter exploitative behav Method 2008) In the research reported here.we explored the p Participants bility that gossip Two hundred sixte participants (82 male 134 female mean age=20.4 years)took part in this study in retum for tion. a flat payment of $5 and the opportunity to eam an addi tional payment ranging from approximately $2 to $12 made aware of others'past behavior throughg in they will use this information as a guide for selectively inte Procedure ostracizing thos partici oups by allowing moresco ratory at a lange public university.The experimente seated all participants at separate computer stations and efts of group efforts while avoiding exploitation. requested that they not verbally communicate with any one else at any um mente free riding means of social and economic punishment ducted using the computer and directed them to follow individuals cannot reap the benefits of group efforts the directions presented on the computer in front of (Ouwerkerk,Ker, Gallucci,van Lang 2005:Spoor them 200 disi er comple ting basi activates neurological responses analogous to pain 4 participants each.Each participant received an allot. with physica injury (Eis ment of 10 points at the beginning of each round of the ry. 2005 oint was wo L p risn igh th up fund and ho which will lead ostracized individuals to cooperate at to keep for themselves.Whatever number of points all 4 higher levels in subse equent group settings.We therefor participants contributed to the group fund as a whole expect that gossip and n wil espe ly we as then ao and redist ute C: equal and ostra up me rcise this pnd cism provides a means for partner selection. vidual participants will benefit the most by selfishly free To test these claims,we conducted a large-scale group- riding off of everyone else's contributions while contrib. study.In each round or the st em Fehr Gachter,2002:Weber s hat efit th dy.pb public-s next round.in which they interacted with an entirelydif exercise all participants completed a five-question ferent group.The study featured two treatment condi- comprehension check.The computer displayed a mes- and one both they hac uld m about one of their current group members to that per ticipants had successfully completed the comprehensior son's future interaction partners Additionally,in one check,they were provided with a practice round of the treatment condition,recipients o I info public-goods exercise to familiarize them with the com- ction by2 Feinberg et al. ethnographic evidence suggests that group members readily spread reputational information about and stig￾matize those who do not conform to normative levels of cooperation (Wilson, Wilczynski, Wells, & Weiser, 2000). In addition, experimental studies have investigated the link between gossip and cooperation, finding that gossip can facilitate indirect reciprocity (Sommerfeld, Krambeck, Semmann, & Milinski, 2007) and deter exploitative behav￾ior in groups (Beersma & van Kleef, 2011; Feinberg, Willer, Stellar, & Keltner, 2012; Piazza & Bering, 2008). In the research reported here, we explored the possi￾bility that gossip promotes cooperation by facilitating partner selection. We hypothesize that gossip fosters and sustains high levels of cooperation when paired with a means for social exclusion. Specifically, if individuals are made aware of others’ past behavior through gossip, they will use this information as a guide for selectively inter￾acting with only those people known to be cooperative, ostracizing those known to be defectors. As a result, we expect such reputational-information sharing to promote cooperation in groups by allowing more cooperative individuals to exclude free riders and thus reap the ben￾efits of group efforts while avoiding exploitation. Additionally, ostracism should serve as a powerful tool for mitigating free riding. Social exclusion is an effective means of social and economic punishment. Ostracized individuals cannot reap the benefits of group efforts (Ouwerkerk, Kerr, Gallucci, & van Lange, 2005; Spoor & Williams, 2007; Williams, 2007), which makes the threat of expulsion a strong disincentive to defection. Beyond its economic effects, research has shown that social exclusion activates neurological responses analogous to pain responses associated with physical injury (Eisenberger, Lieberman, & Williams, 2003; MacDonald & Leary, 2005). Thus, it is likely that people will find that the costs of ostra￾cism outweigh the potential benefits for selfish behavior, which will lead ostracized individuals to cooperate at higher levels in subsequent group settings. We therefore expect that gossip and ostracism will work especially well in tandem, because gossip facilitates diffusion of informa￾tion about formerly exploitative group members and ostra￾cism provides a means for partner selection. To test these claims, we conducted a large-scale group￾interaction study. In each round of the study, participants decided whether or not to make a costly contribution that would benefit their group before moving onto the next round, in which they interacted with an entirely dif￾ferent group. The study featured two treatment condi￾tions and one control condition. In both treatment conditions, prior to the beginning of a subsequent round, group members could relay reputational information about one of their current group members to that per￾son’s future interaction partners. Additionally, in one treatment condition, recipients of this reputational infor￾mation could use it as a means for partner selection by excluding one of the prospective group members. We hypothesized that when participants could relate reputa￾tional information and recipients could act on the infor￾mation they received by ostracizing a suspect group member, groups would achieve significantly higher levels of cooperation. Method Participants Two hundred sixteen participants (82 male, 134 female; mean age = 20.4 years) took part in this study in return for a flat payment of $5 and the opportunity to earn an addi￾tional payment ranging from approximately $2 to $12. Procedure The study involved nine separate groups of 24 partici￾pants each and was run in a behavioral-economics labo￾ratory at a large public university. The experimenter seated all participants at separate computer stations and requested that they not verbally communicate with any￾one else at any time during the study. The experimenter then informed participants that the study would be con￾ducted using the computer and directed them to follow the directions presented on the computer in front of them. After completing a basic demographic questionnaire, participants learned how to play a public-goods exercise (Fehr & Gachter, 2002). The exercise involved groups of 4 participants each. Each participant received an allot￾ment of 10 points at the beginning of each round of the exercise. Each point was worth 2.5¢. All 4 participants then determined how many of their 10 points they wished to contribute to a group fund and how many they wished to keep for themselves. Whatever number of points all 4 participants contributed to the group fund as a whole was then doubled and redistributed equally to each group member. Researchers commonly use this public￾goods exercise to examine social dilemmas because indi￾vidual participants will benefit the most by selfishly free riding off of everyone else’s contributions while contrib￾uting nothing themselves (Fehr & Gachter, 2002; Weber, Kopelman, & Messick, 2004). After learning how to play in the public-goods exercise, all participants completed a five-question comprehension check. The computer displayed a mes￾sage informing participants which questions they had missed (if any) and re-presented each of these ques￾tions until they selected the correct answer. Once par￾ticipants had successfully completed the comprehension check, they were provided with a practice round of the public-goods exercise to familiarize them with the com￾puter interface. Downloaded from pss.sagepub.com by Cai Xing on February 13, 2014