Social goals as triggers of cooperation: How reciprocity and group solidarity encourage cooperative behavior in a public goods game

Transcription

1 Social goals as triggers of cooperation: How reciprocity and group solidarity encourage cooperative behavior in a public goods game Dr. Julie Urda Rhode Island College Providence, RI, USA jurda@ric.edu Dr. Christoph H. Loch INSEAD Fontainebleau, France christoph.loch@insead.edu Keywords: social goals, social dilemmas, reciprocity, group solidarity, cooperative behavior

2 ABSTRACT Social dilemmas are situations in which each decision maker is best off acting in his own self-interest, regardless of what other persons do [but] in which everyone would have done better had they decided not to act in their own private interest (van Lange et al., 1992, p. 4). Thus, social dilemmas, in the form of experimental games, have long been used to test for competitive versus cooperative behavior among individuals within groups. Because defecting is the dominant strategy, it is the expected individual behavior in social dilemma games. Many studies have been conducted to discover what factors encourage the cooperative behavior (see Messick & Brewer, 1983 and van Lange et al., 1992 for reviews) that is still observed. While previous studies have shown evidence that reciprocity (Axelrod, 1981), group identity (Dawes et al., 1988) and their relative social motives (Liebrand, 1984) all may affect people s choices in social dilemmas, the results are explained as rational strategies (Axelrod, 1981) or post-hoc explanations (Kerr & Kaufman- Gilliland, 1994). In this study, we specifically test for the effects of reciprocity and group solidarity as ends in themselves on behavior in social dilemmas. People have fundamental social goals status, reciprocity, and group solidarity that, in addition to striving for individual resources, influence their behavior in social dilemmas. Social goals are fundamental goals that become salient to individuals only when they interact with others. While these goals evolved in us as primary survival goals, today, these goals have become proximate goals goals pursued by individuals as ends in themselves in social situations regardless of other functional benefits that accompany their achievement. In this paper we establish that the social goals of reciprocity and group solidarity encourage cooperation in social dilemmas. People reciprocate favors not necessarily to maintain relationships or garner future favors; the act of reciprocating is a goal in itself. Group-oriented behavior exists despite temptations for opportunism because group solidarity has developed as a basic goal in its own right. We hypothesized that people who played minimal interaction, one-shot, public goods, social dilemma games in which reciprocity or group solidarity were emphasized would behave significantly more cooperatively than those in control groups. We also hypothesized that these results would obtain across national cultural differences. In the experimental conditions, reciprocity was operationalized by emphasizing a history of friendliness and helpfulness between players; group solidarity was operationalized by emphasizing interdependence among members and group uniqueness. Results show people did behave more cooperatively when the reciprocity and group solidarity social goals were made salient than in control groups. Manipulation checks show subjects did distinguish between reciprocity and group solidarity situations, so any similarities that might have existed between manipulations did not confound the results. Finally, the same pattern of behavior was found in both French and Danish populations, indicating the results are robust to cultural differences. These combined results provide evidence that cooperation in social dilemmas can be manipulated by making social goals salient. In other words, cooperation can be enhanced by stimulating people s fundamental goals of reciprocity and group solidarity. -1-

3 INTRODUCTION What are social goals? Without question, reciprocity and group solidarity are well-covered topics in the social science literature. However, the psychological mechanisms that support these behaviors have not been studied directly. One of these psychological mechanisms is social goals (Kenrick, Maner, Butner, Li, Becker & Schaller, 2002). Social goals are goals that place predictable constraints on emergent processes within and between individuals, influencing their dynamics over the short-term, and across developmental and evolutionary time scales (Kenrick et al., 2002, p. 1). Because social goals require an individual to interact with others to become salient, they differ from individual goals that tend to be economic in nature. Individual goals, such as nourishment, sleep, and reproduction, do help us survive and do often involve social interaction. However, their pursuit is economic in nature in that people act on these goals for their own well being regardless of their social context. Social goals take into account the fact that people behave in ways that do take into consider their social environment when making behavioral decisions. Kenrick et al. (2002) describe six social goals, each linked neurologically to an adaptive problem in human evolutionary history: mate choice, relationship maintenance, offspring care, status seeking, coalition formation and self-protection. Our research focuses on goals similar to coalition formation (reciprocity), to form and maintain cooperative alliances, and self-protection (group solidarity), to protect oneself and alliance members against threats to survival or reproduction (Kenrick et al., 2003). Our notion of social goals is somewhat different. We posit that social goals, which originally evolved biologically to enhance survival, have developed into goals pursued as ends in themselves, regardless of their functional origins. Although all modern humans have the same psychological mechanisms adapted to social domains as did ancestral humans, the characteristics of -2-

4 modern social situations are quite different. Psychological mechanisms such as social goals evolved in the human brain as means to the ultimate goal of survival. However, modern humans do not necessarily need the same behaviors to survive today that they did in evolutionary history. For instance, modern humans often help strangers in need. As an ultimate goal for survival, such behavior does not make sense: helping an unknown other bears a (survival reducing) cost to the self while providing a (survival improving) benefit to another. But as a proximate goal, pursued as an end in itself regardless of other functional benefits that accompany their achievement, it does make sense. As a part of human biology, although pursuit of social goals is no longer strictly a means to survival, it still affects human behavior. Social goals and behavior in social dilemmas Individual goals and social goals both help humans survive, but they often conflict with each other. What is best for us as individuals is not always best for others in our social environment, and may even be detrimental to them. Likewise, when we act in the interest of the group, it often requires self-sacrifice. Situations in which individual goals are at odds with social goals are called social dilemmas because a) each individual receives a higher payoff for a socially defecting choice than for a socially cooperative choice, no matter what the other individuals in society do, but b) all individuals are better off if all cooperate than if all defect (Dawes, 1980, p. 169). Figure 1 represents the type of social dilemma called a public goods game that we use in this study. If everyone contributes, everyone is much better off; but those who do not contribute keep their endowment and still receive a payoff. Examples are public television and public radio. If you are the only one who gives, everyone gets a small share of the public good at your expense. If you are the only one who keeps your endowment, you get a large share of the public good in addition to the money you saved by not contributing. Because there is no way of enforcing giving, a -3-

5 dilemma arises: do I contribute in hopes that everyone else will give, too? Or, do I keep my contribution and reap the benefits of others contributions? The dominant strategy under economic rationality is, of course, the latter. But if everyone follows the dominant strategy, the group, as a whole, loses because there are no contributions available to provide the public good. However, when considering the social context of the situation, social goals are triggered. The social goals of reciprocity and group solidarity make the situation not about what is best for the individual, but rather what is best for the social group. Considering the group over the self makes giving a more reasonable strategy. The question now is, under what conditions do social goals supercede individual goals? In this paper, we find that minimal social interaction can be enough to make social goals a stronger influence on behavior than individual goals. Maximum possible payout Dominant strategy under economic rationality Keep E + (n-1) 2E n Give Individual may receive >> E Personal benefit > helping others Helping others > personal benefit Individual Others Helping others > personal benefit Personal benefit > helping others Give Keep 2E Individual may receive < E n Maximum possible payout Figure 1: A public goods social dilemma, where E = initial endowment and n = number of players -4-

6 REVIEW OF THE LITERATURE Reciprocity and group solidarity as social goals That people strive for reciprocity, ensuring fairness and equity in exchange relationships, is a well-established social norm (Gouldner, 1960). Trivers (1971) theorized that reciprocal altruism, helping others to the detriment of one s own well being with the expectation of returned future favors (Frank, 1988), can exist as an evolutionary stable strategy if people live in close proximity, are interdependent, and can remember others past behavior. Sober & Wilson (1998) show mathematically that reciprocal altruism can thrive in groups despite intrusion of cheaters. Empirically, Cosmides & Tooby (1992) show a psychological mechanism has evolved to identify cheaters. The details of this research explain why people will help others even if cheaters exist in their society and even at a cost to themselves. We assert that although reciprocity (tit-for-tat behavior) originated as a function for survival, today it has evolved into a proximate goal of reciprocal altruism (doing something for another at a cost to the self, with some expectation of a similar favor in the future). While it may be argued that these two goals are separate, in both cases one person acts cooperatively first and then waits for the responses of others. In this respect, reciprocity is neither selfish nor altruistic; people merely act in the interest of others because they feel it is a good thing to do. This behavior is reasonable and easy to explain if we consider that reciprocity is fulfilled not necessarily because social norms tell us to return favors, nor because we want immediate and exact repayment, nor because it puts us on moral high ground, but rather because reciprocity fulfillment is pursued in its own right. People also pursue group solidarity, awareness of and attraction toward an interacting group of interdependent members by self-identified members of that group (Bouas & Arrow, 1996, pp ). People who identify themselves with a particular group think of themselves as -5-

7 interdependent members of that group and behave cooperatively with its other members. Baumeister & Leary (1995) and Stevens & Fiske (1995) argue that, as strong indicator of selfidentity, the sense of belonging to a group has proved to be essential people s sense of human health and well-being. Empirical evidence shows people feel affiliation with strangers who share attitudes (Park & Schaller, 2005) or arbitrary characteristics (Kurzban, Tooby & Cosmides, 2001). These results imply people have a natural tendency to affiliate with like others on the basis of their similarity alone, not necessarily for any economic benefit associated with doing so. The implication of group solidarity in our research is not that people strive to attain group solidarity, but rather that people strive for the group, including themselves, to fare well as a whole. Having group solidarity has clear indications for survival: the more resources your group can attain and the stronger it is to defend them, the better off everyone is not only in the short term but also in the future (the healthier you are the more chance of passing on your genes the healthier the next generation, and so on). However, being a member of the group is not enough to survive. There must be solidarity as well, not only to work together to gain and defend resources, but also to overcome individual drives to free-ride or, worse yet, collaborate with rival groups. As social groups (as opposed to family groups) grow in size and scope, opportunistic behavior becomes more difficult to police. It makes sense, therefore, that as social groups evolved, so did the group solidarity goal to override temptations to act individualistically and to encourage group solidarity. As a whole, the research shows ensuring reciprocity and maintaining group solidarity are social behaviors pursued for their own sake, not necessarily for the benefits gained or the disadvantages avoided through them. Therefore, the roots of these goals are essentially biological in nature and inherent in all humans. We argue that reciprocity and group solidarity influence people s behavior in social dilemmas. When a person s behavior increases goal satisfaction, that person will continue to do whatever it is that sustains this satisfaction. When reciprocity and group solidarity are -6-

8 made salient as social goals, people choose to cooperate because doing so improves the satisfaction of these goals. Social dilemma games While the results of previous studies that use SDGs have shown reciprocity and group solidarity, and their relative social motives all affect people s choices in social dilemmas, none of them specifically tests for the influence of social goals on behavior. In research on how information presentation affects people s behavior in social dilemmas, Axelrod (1981) showed that a tit-for-tat strategy, in which a player cooperates in the first round and then mirrors the other player in subsequent rounds, is the only collectively stable strategy for cooperators among competitors in multiple-round, two-person SDGs. In their research on the effects of communication within groups on competition and cooperation in SDGs, Dawes, Van de Kragt & Orbell (1988) showed that cooperation within groups is significantly higher when members of the same group are allowed to communicate before making their decisions in SDGs than when groups are not allowed to communicate. The authors suggest that communication among group members creates group solidarity, which then gives rise to the observed results. Finally, Liebrand (1984) looked at the effects of social motives on competition and cooperation in a multiple-round SDG in terms of relative and absolute measures. He also established a continuum of degree of cooperation by social motive: altruists give the most, followed by cooperators, then individualists and finally competitors. Previous studies have found effects of social goals on behavior either as rational strategies (e.g., Axelrod, 1981) or post-hoc explanations (e.g., Dawes et al., 1988) for general results obtained while looking for factors that affect the outcomes of SDGs. While there have been several important studies specifically regarding the effects of group solidarity on social dilemma behavior, they either do not rule out the impact of future consequences on behavior (Brewer & Kramer, 1986; -7-

9 Kramer & Brewer, 1984), or they test how other factors change the strength of group solidarity s influence on behavior (Dawes et al., 1988; De Cremer & Van Vugt, 1999). Thus, there may be other factors that interact with group solidarity to cause the observed results. We specifically test for the effect of social goals as ends in themselves on social behavior. Previous studies (with the exception of Dawes et al., 1988) that find effects for reciprocity and group solidarity on social dilemma behavior have tested hypotheses using multiple-trial games (Axelrod, 1981; Brewer & Kramer, 1986; Isaac, Walker & Williams, 1994; Kerr & Kaufman- Gilliland, 1994; Kramer & Brewer, 1984). Thus, the benefit of information enters into the decision making process. Our research differs in that the effects of social goals obtain in a one-shot, public goods game; players do not have information regarding the behavior of other players to help them make their decisions. Finally, virtually all previous social dilemma studies focus on only one manipulation at a time, usually to see how other factors affect its potency (Dawes, McTavish & Shaklee, 1977; Isaac & Walker, 1988; Isaac, Walker & Williams, 1994; Kramer, 1991; Sally, 1995). Liebrand (1984) does study the effect of the four social motives on social dilemma behavior, but he compares all manipulations to the group average and finds only ordinal differences between conditions. He does not clarify whether differences between manipulations are significantly different from each other, nor does he distinguish the individual effects of each manipulation on behavior. Our research tests for the effect of each social goal on behavior, separately and despite the possible presence of the other social goals. The results of each manipulation are compared to the same control group. In comparing each manipulation to the same control group, our research shows reciprocity and group solidarity each has its own effect on behavior separately from or despite effects of the other. -8-

10 HYPOTHESES We hypothesize that reciprocity and group solidarity directly affect cooperative behavior in social dilemmas. Our test situations were designed to maximize the effects of these social goals alone and to minimize subjects considerations of future benefits and disadvantages in their decision making process. By comparing the results from each social goal manipulation to a single control we can see whether each social goal we study influences behavior separately from and despite the presence of the other. A mechanism that appears to be essential for cooperation to become a stable strategy in human groups is strong reciprocity. Strong reciprocity is defined as: a combination of altruistic rewarding, which is a predisposition to reward others for cooperative, norm-abiding behaviors, and altruistic punishment, which is a propensity to impose sanctions on others for norm violations. Strong reciprocators bear the cost of rewarding or punishing even if they gain no individual economic benefit whatsoever from their acts (Fehr & Fischbacher, 2003, p. 785). In other words, strong reciprocators act to maintain fairness in social interactions regardless of any benefits or disadvantages doing so might bring them. This mechanism supports the notion that reciprocity is pursued as a goal in itself. Strong reciprocity, in turn, works through several other mechanisms including reputation formation, indirect reciprocity and third party punishment. Reputation formation works by labeling defectors as cheaters among their peers. In future interactions others are unlikely to cooperate with those with a reputation for cheating. Thus, those who want to receive help from their peers in the future will cooperate in the present so as not to gain reputations as cheaters (Fehr & Fischbacher, 2003). Indirect reciprocity works in a similar way. People are more likely to help others who have developed a reputation for costly cooperation in the past than those who have not. That their peers will be more likely to help them in the future if they cooperate thus is an incentive for people to -9-

11 behave cooperatively in the first place (Panchanathan & Boyd, 2004). Finally, third party punishment works much like reputation except third party punishers (see Fehr & Gächter, 2002) are so-called disinterested third parties who punish even though they are not involved in the social interaction and punishing is costly to them (Fehr & Fischbacher, 2004). In other words, they put themselves at a disadvantage to benefit others. Third party punishers, therefore, reinforce cooperation twice over: first by punishing cheaters, second by building their own reputations as cooperators. The dual goals of being labeled a cooperator and avoiding being labeled a cheater thus allow cooperation to become a stable strategy among humans. The existence of such strong reciprocity implies humans are driven by goals to maintain reciprocity by behaving cooperatively. Furthermore, when reciprocity is salient to people, i.e., when they believe they are interacting with others with whom they have interacted in the past and who have proven to behave fairly in the relationship, they will cooperate with them. The hypothesis is that people will choose the cooperative option in a social dilemma if they believe they and their fellow players have had a previous positive relationship, even if this relationship is imagined and fleeting. Thus, Hypothesis 1 (H1): When people believe they are friendly with others or have had cooperative relationships with them in the past, they will have a higher tendency of putting their endowment in the common pool (versus keeping it) than when there is no previous history between players. The need to belong has been shown to be a significant and strong motivator of human social behavior. A series of studies by Tajfel (1970; Billig & Tajfel, 1973; Tajfel & Billig, 1974; Tajfel, Billig, Bundy & Flament, 1971) provides ample evidence that people do have a tendency to divide their social world into in-groups and out-groups; that these distinctions may be based on highly arbitrary and trivial criteria; and that in-group members are willing to contribute to their in-group as a whole even if it means giving up some individual benefit. These studies also show people will be willing to give up their individual benefits for the sake of their in-group if it means their group will receive more than other groups (out-groups). -10-

12 While most work on cooperative behavior has focused on reciprocity, recent research on group affiliation (Bernhard, Fehr, & Fischbacher, 2006) shows that it, too, is a strong motivator of cooperative behavior. Through a series of comparisons both within and between groups with strong identities, Bernhard, Fehr, & Fischbacher (2006) show that third party punishment enhances group cooperation norms. The authors argue that this tendency evolved as a goal in humans because it enhances group (and therefore individual) survival. In other words, individuals pursue group solidarity by cooperating with the group, thus reducing the threat of exclusion from it and increasing chances of survival. Even more interesting is the finding that whether the victim or the defector is a member of a third party s in-group also determines the level of third party punishment (which, as mentioned above, is considered a form of cooperation) observed. If the victim is a member of the third party s in-group, the third party will punish the defector more heavily than if the victim is in the third party s out-group regardless of whether the defector is in the third party s in-group (Bernhard, Fehr, & Fischbacher, 2006). These results imply that when group solidarity is salient to people, i.e., when they believe they and their groupmates have a unique characteristic in common, and that this characteristic is different from other groups, they will behave on behalf of their group even if it means foregoing some individual benefits. The hypothesis is that people will choose the cooperative option in a social dilemma if they believe they and their fellow players constitute a real group and that they have something unique in common, even if this characteristic is arbitrary and trivial such as a group name. Hypothesis 2 (H2): When people believe they are part of group salient to them, in which members have a unique, common characteristic, they will have a higher tendency of putting their endowment in the common pool (versus keeping it) than when there are no indicators of group solidarity. To be considered biologically evolved, a psychological mechanism needs to be shown present in human beings across demographic lines. Because the salience of each social goal is, in part, culturally determined, it is necessary to calibrate tests on different populations to their cultural -11-

13 differences. However, if the basic test is held constant and only the cultural context is changed, the same results should obtain across populations if the psychological mechanism is biologically based (Cosmides & Tooby, 1992; Hofstede, 1997; Scherer, Wallbott & Summerfield, 1986). We tested our hypotheses in two relatively different cultures: France and Denmark. The instrument was calibrated for subjects from a given population, in a lab, in France. We conducted the same study in Denmark, but, due to time and budget constraints, without calibrating the instrument for different test conditions or cultural contexts. However, finding similar and significant results in both France and Denmark under these more conservative conditions would only show robustness for the results. Hypothesis 3 (H3): Results obtained in testing H1, and H2 in one population should also obtain in alternative populations (controlling for cultural differences). METHODOLOGY Independent variable The independent variable was manipulation type. There were two manipulations, reciprocity and group solidarity, each compared to the control condition. The manipulations themselves were paragraphs added to the control condition task instructions (Appendix A). Each paragraph was designed to make one social goal significantly more salient than the other social goals. Reciprocity was operationalized via prior helping behavior and friendliness by adding a paragraph to the instructions that told subjects the other people in the study should be considered their friends and that they had helped each other when in need in the past. Subjects were then asked to introduce themselves (by first name only) and shake hands with each other to get to know each other better. The written manipulation and brief encounter were designed to make reciprocity salient even under conditions of assumed prior interaction. -12-

14 Group solidarity was operationalized via solidarity and uniqueness by adding a paragraph to the instructions that told subjects they comprised a real group and reminded them the group would receive a higher payout as a whole if everyone contributed to the common pool than if everyone kept their endowment. Subjects were also told that as part of the study their results would be compared to those of other groups so they should take one minute to choose a group name in order to distinguish their group from others. This manipulation was designed to encourage solidarity by reminding subjects that their payouts were interdependent, and to make group solidarity salient by giving them a trivial but common defining characteristic (group name). Dependent variable The dependent variable (Response) was the degree to which subjects behaved competitively or cooperatively in a public goods game. Response was indicated via the answer given on a scale as to how certain subjects were in choosing whether to keep their endowment or put it in the common pool. Subjects were given a 7-point Likert-type scale that ranged from I am absolutely certain I want to keep my endowment to I am absolutely certain I want to put my endowment in the common pool as anchors. The scale was not marked with numbers so as not to imply any answer had a different value than any other. Subjects were told all options were equally normal and legitimate as responses (Appendix A). Values of -3 to 3 were assigned to the Response scale ex-post for analytical purposes. Instrument The instrument was a public goods SDG based on those described by Dawes (1980). In the basic scenario, subjects are given an endowment (E), which they can choose either to keep for themselves or to put into a common pool. The total of the endowments put in the pool is doubled and then divided equally among the four subjects regardless of each individual player s choice. Thus, -13-

15 even subjects who choose to keep their original endowment receive their share of the pooled funds. Subjects who put their endowment in the pool receive only half of it in return ((E*2)/4) as part of their share of the pooled funds. Subjects who keep their endowment receive all of it plus their share of the pooled funds. Therefore, the dominant strategy is to keep the endowment. The more subjects put their endowment in the pool, the higher the endowment to the group as a whole. However, by putting their endowment in the pool, subjects risk losing half of it if they are the only person to do so. The dilemma is whether to keep the endowment to gain the most for yourself at the expense of the group, or to put the endowment in the pool to improve the group gain at your individual expense. We specifically chose to test this situation as a one-shot rather than multiple trial game to rule out effects of additional information about others choices as causes of behavior. French study: Testing H1 & H2 Subjects Subjects were 108 people recruited off the street near a French university. The majority were students (92%) and French nationals (85%). The average age of all subjects was 23 years; 42 percent were male. Subjects were told they would receive between 5 and 25 euros (approximately $6-$31), in the form of cinema vouchers, for their participation time (15-30 minutes). The actual payouts subjects received depended on the combination of their own decision and those of the others in their group. Procedure The procedure was to recruit subjects, assign them to conditions randomly, and ask them to make a decision independently yet simultaneously with three other subjects. The decision was based on a public goods social dilemma. To control the amount of interaction between subjects, subjects were recruited individually, brought to the lab independently of each other, seated so they could not -14-

16 see each other, and were not allowed to talk to each other unless the instructions required it. After subjects signed a consent form, the study director handed them a booklet in French 1 comprising a description of their task, a scale for indicating their decision, manipulation checks, feedback solicitations, and demographic questions (Appendix A). The study director then explained the task and payout matrix, both orally and visually, ensured the subjects understood the game, and clarified any questions they had. For the control condition, there was no interaction among participants at all. For the reciprocity and group solidarity conditions subjects were allowed to interact under strict guidelines and supervision. In the reciprocity experiment, subjects were allowed one minute to introduce themselves and shake hands, but not talk about anything else. In the group solidarity experiment, subjects were given one minute to choose a group name, but not talk about anything else. Subjects then completed the task, and were compensated, debriefed, and dismissed. Danish study: Testing H1, H2 & H3 Subjects Subjects were 93 English-speaking graduate students at a Danish university. The majority were Danish nationals (65%), the average age of all subjects was 24 years, and 75 percent were male. Subjects were recruited in the university s cafeteria and told they would receive between 50 and 250 Danish kroner (approximately $8-$42), in the form of movie rental vouchers, for their participation time (15-30 minutes). The actual payout individual participants received depended on the combination of their own decision and those of the others in their group. 1 The instruction and response booklet and manipulation scenarios were written in English by a native speaker, then translated into French by a native French speaker with translating experience. The booklet was then given to other native French speakers to test that it was readable and made sense to native French speakers. -15-

17 Procedure The procedure was to recruit subjects, assign them to conditions randomly, and ask them to make a decision independently yet simultaneously with the three other subjects. The decision was based on a public goods social dilemma. Subjects arrived at the lab in half-hour intervals. When they arrived they were immediately greeted and seated so as to minimize the amount of interaction between them before the experiment began. The rest of the procedure is the same as in the French study, except the instruction booklet and all oral communication were in English. RESULTS All analyses were completed using SPSS version The nature of the experiment led the data to skew right to a degree that could not be normalized using the usual transformations. Therefore, we used the non-parametric Mann-Whitney U (MWU) test. Instead of comparing cell means to determine significant differences between two data sets, it uses cell medians to check for significant differences between data sets. This test is more robust to severe skewing than ANOVAs. Regression analyses revealed no systematically significant effects of subjects sex, nationality, or work situation in either study. French study: H1 & H2 Descriptive statistics and the canonical correlation for the entire data set are shown in Tables 1 and 2, respectively. Over all conditions, the mean response was 0.40, and responses covered the entire 7-point scale. -16-

18 Table 1: Descriptive statistics French study Mean Skewness Condition N Statistic Std. Error Std. Dev. Statistic Std. Error Control Reciprocity Group identity Table 2: Pearson correlations French study Control Reciprocity Reciprocity Group identity Note: There were no significant correlations. Response was significantly different for the reciprocity manipulation than for the control condition (Table 3; p <.001). Thus, the reciprocity manipulation, i.e., making subjects believe they had a prior positive relationship with each of their fellow players, did encourage subjects to make the cooperative decision (to put their endowment in the common pool) more than subjects did in the control condition. Therefore, reciprocity did influence behavior and H1 that reciprocity encourages cooperative behavior in SDGs, is supported. Manipulation checks showed the reciprocity manipulation (Table 4; p <.001 vs. group solidarity) did transmit its intended message. These results imply the reciprocity manipulation caused the observed effect. Response was significantly different for the group identity manipulation than for the control condition (Table 3; p <.001). Thus the group identity manipulation, i.e., making subjects believe they were part of a real group, did encourage subjects to make the cooperative decision (to put their endowment in the common pool) more than subjects did in the control condition. Therefore, group identity did influence behavior and H2, that group identity encourages cooperative behavior in -17-

19 SDGs, is supported. Manipulation checks showed the group identity manipulation (Table 4; p <.001 vs. reciprocity) did transmit its intended message. These results imply the group identity manipulation caused the observed effect. Table 3: Results French study Results Comparison N MWU Z Sig. Reciprocity vs. Control Group identity vs. Control Table 4: Manipulation checks French study Significance vs. Other Manipulations Condition Reciprocity Group identity Reciprocity Group identity Danish study: H1, H2, & H3 Descriptive statistics and the canonical correlation for the entire data set are shown in Tables 5 and 6, respectively. Over all conditions, the mean response was 0.79, and responses covered the entire 7-point scale. -18-

20 Table 5: Descriptive statistics Danish study Mean Skewness Condition N Statistic Std. Error Std. Dev. Statistic Std. Error Control Reciprocity Group identity Table 6: Pearson correlations Danish study Control Reciprocity Reciprocity Group identity Note: There were no significant correlations. Response was significantly different for the reciprocity manipulation than for the control condition (Table 7; p <.05). Thus the reciprocity manipulation, i.e., making subjects believe they had prior positive relationships with each of their fellow players, did encourage subjects to make the cooperative decision (to put their endowment in the common pool) more than subjects did in the control condition. Therefore, reciprocity did influence behavior and H1 is supported. Manipulation checks showed the reciprocity manipulation (Table 8; p <.001 vs. group solidarity) did transmit its intended message. These results imply the reciprocity manipulation caused the observed effect. Table 7: Results Danish study Results Comparison N MWU Z Sig. Reciprocity vs. Control Group identity vs. Control

21 Table 8: Manipulation checks Danish study Significance vs. Other Manipulations Condition Reciprocity Group identity Reciprocity Group identity There was a marginal but significant difference for Response between the group solidarity manipulation and the control condition (Table 7; p <.10). Thus the group solidarity manipulation, i.e., making subjects believe they were part of a real group, did encourage subjects to make the cooperative decision (to put their endowment in the common pool) more than subjects did in the control condition. Therefore, group solidarity did influence behavior and H2 is supported. Manipulation checks showed the group solidarity manipulation (Table 8; p <.05 vs. reciprocity) did transmit its intended message. These results imply the group solidarity manipulation caused the observed effect. The combination of the results of both the French and Danish studies supports H3 that the same results should obtain in different populations if the psychological mechanism is biologically based. Finding the same overall pattern in two different cultures implies some support for the biological nature of social goals. Clearly this methodology needs to be applied to populations in many other cultures to truly test the cross-cultural consistency hypothesis. DISCUSSION The results of these two sets of experiments show the social goals of reciprocity and group solidarity can be made salient enough to encourage cooperation in social dilemmas. Using social goal salience to influence behavior in social dilemmas is a new approach to social dilemma research. In -20-

22 addition, these results provide preliminary support that social goals are biologically based. We will now discuss each of these findings in turn. Reciprocity That the reciprocity manipulation obtained the expected results implies that in situations in which people have a history of positive relationships or are friendly with each other, people will be more likely to cooperate than when they have no such history. This result obtains even when contact is minimal, when it is unlikely that, in reality, subjects will encounter one another again, and when there is no guarantee that others will cooperate as well. Results from the French study provide support the hypothesis that the reciprocity social goal influences behavior in social dilemmas. Subjects in the French study did not know each other beforehand and were not allowed to interact until the study director asked them to introduce themselves. While the instructions asked subjects to consider they had positive helping and friendship relationships with the other subjects as well, previous studies showed this indication alone was not salient enough to encourage cooperation significantly. In pilot studies, in which subjects were kept completely separate from each other, post hoc questioning revealed that subjects did not feel the situation was real enough to make themselves believe it. Only when subjects were allowed to interact did the reciprocity social goal become salient. This result makes sense by definition: social goals are goals that require an individual to interact with others to become salient. That such strong results obtained, even though the situation was contrived and contact was minimal, shows how robust reciprocity can be once made salient. Of particular interest is that stronger support was found for the reciprocity hypothesis in the French study than in the Danish one. In the French study subjects were recruited separately and allowed to interact with each other only under the study director s strict instructions and supervision. In contrast, subjects in the Danish study were often recruited in previously-formed friendship or study groups, which obviously allowed them to interact before the experiment began. -21-

23 We would expect the tendency to cooperate under the reciprocity condition to be higher in situations in which people already have a positive history of working together. That the strength of the Danish results was lower than that of the French results can be explained by two ceiling effects. First, because subjects had worked or were friends with each other before the study, the effect of the reciprocity manipulation during the study made less of a difference between the control group and the manipulation group. The manipulation itself still had an effect, but it was diluted by the subjects having prior relationships. Second, an instrument calibrated to a different population was used. The reciprocity manipulation was developed to be applicable to French subjects. It was not changed to account for cultural differences that may impact the meaning of the reciprocity situation to Danish subjects. Thus, the salience of the reciprocity social goal as given in the test instrument may not have worked the same on Danish subjects as on French ones. Both of these effects could have made the control condition move in the direction of cooperation. Therefore, a significant difference between the manipulation and control conditions for reciprocity (which encourages cooperation) would be more difficult to obtain. However, the fact that significant results did obtain, despite these more conservative conditions, further indicates the robustness of the effect the reciprocity social goal has on behavior. Group solidarity The group solidarity manipulation also produced results that support our hypotheses. Although there was no reason for subjects not to keep their endowment for themselves, they still contributed to the group-at the risk of losing half their endowment-significantly more when group solidarity was made salient than when there was no indication of group membership. Subjects had no contact with each other before the study and group membership was contrived (they were told they were a group) and trivial (they happened to be recruited in chronological proximity). There was no group identification before participants were assembled and the group would cease to exist once -22-

24 their session had ended. Subjects were assured that none of the other participants would know their responses and would most likely not encounter each other afterwards. Less than one minute of interaction requiring joint effort to determine an identity (choosing a group name) was enough to make subjects choose the cooperative option in a social dilemma significantly more than control subjects. These results support the hypothesis that once even minimal group solidarity is established people will behave on behalf of the group with which they identify. Thus, the group solidarity social goal itself appears to influence behavior significantly in social dilemmas. The Denmark study also supports our hypothesis regarding group solidarity. That significant results obtained in a similar but uncalibrated study shows the robustness of group solidarity in encouraging cooperative behavior. However, that the results of the Danish study are marginally significant is a bit puzzling considering Danish subjects were often recruited in pre-existing friendship or study groups. On the one hand, we might expect results from subjects who already had a history of working together as a group to be stronger than those from a contrived group. Such results would be expected when comparing each type of group (history vs. no history) to a single control condition. On the other hand, in the Denmark study it is not unreasonable for the comparison between the group solidarity manipulation and the control condition to be significant but appear weaker than for the same comparison in the French study. The same ceiling effects would affect the group solidarity condition as the reciprocity condition. Because subjects already had strong identities with their group, their department, their university, etc., they were automatically more likely to identify with each other on one of these levels before they even entered the lab, thus raising the natural level of cooperation. Therefore, the manipulation s contrived grouping would have much less salience compared to a control group assembled under the same conditions than it would have for groups of four randomly selected strangers who had nothing in common before entering the lab. Again, using an instrument not calibrated to control for this situation makes -23-

25 obtaining a significant difference between the manipulation and control condition for group solidarity (which encourages cooperation) more difficult. The fact that significant results did still obtain under these far more conservative conditions shows the robustness of group solidarity s influence on behavior in social dilemmas. Cross-cultural consistency The opportunity to conduct the study in two different cultures allowed us to take a step toward testing our hypotheses for cross-cultural consistency. Our theory of social goals as a psychological mechanism that influences social behavior implies the social goals are hard-wired in all humans. Providing evidence to support this theory requires showing the same results obtain after adjusting the test instrument for cultural differences (Cosmides & Tooby, 1992; Hofstede, 1997; Scherer et al., 1986). The data from these two studies show that reciprocity and group solidarity effectively influence social behavior in two different cultures even though the test instrument was not adjusted for cultural differences. These results, obtained under more conservative conditions than expected, begin to provide evidence that social goals are biologically based. CONCLUSION To the best of our knowledge, it is the only social dilemma study that compares reciprocity and group solidarity both to the same control condition. Previous literature has shown effects for each social goal individually, but does not take into account that other social goal may be active as well and thus interfering with the outcomes. This study is the only one to show that while both social goals may be active in social dilemmas, either one can be made salient enough to influence behavior separately from or despite the impact of the other. These results contribute to the social dilemma literature in that we now know social goals in themselves do influence behavior in social dilemmas, and in that we know they affect social dilemma behavior independently of each other. This last conclusion also contributes to the social goals literature. Specifically, the manipulation -24-

26 checks of all three social goal manipulations showed that they worked independently of each other. The results imply that although either social goal may be active at any time, when one is made particularly salient people act on it independently of the potential influence of the other. This study also provides evidence that social goals are pursued as ends in themselves and regardless of economic incentives. All of the conditions (two manipulations and a control) had the same economic tradeoff at stake yet differences in behavior still obtained when social goals were made salient. Furthermore, these differences obtained under minimal interaction conditions. Reciprocity was made salient merely by telling subjects they were friends allowing them to introduce themselves to each other but otherwise allowing no interaction. Group solidarity was made salient by telling subjects they were part of a group and asking them to choose a group name. Despite these conservative circumstances, subjects in these two manipulation conditions cooperated significantly more than those in the control condition. These results imply that making reciprocity and group solidarity salient changes the interpretation of an essentially economic situation. Remember, the economic tradeoffs were the same in all conditions and the dominant strategy under purely economic rationality-in all conditionswas to compete. When reciprocity and group solidarity were made salient, people considered them, as well as the economic tradeoffs, in making their decision. In other words, the situation ceased to be one of purely economic considerations. If people made their decisions based solely on economic considerations, there would be no difference in behavior between any of the conditions because the economic tradeoffs were the same in all conditions, regardless of whether social goals were made salient. However, we do see a difference in behavior when social goals are made salient even though the economic incentives do not change. These results strongly support the hypothesis that reciprocity and group solidarity significantly encourage cooperative behavior in social dilemma situations. -25-