Reputational advantages and disadvantages of punishment toward norm-violators Yutaka Horita Toshio Yamagishi Hokkaido University 13th international conference on social dilemma Kyoto, 20-24th August 2009

Question ： Is costly punishment sustainable? ➔ Yes, but only when punishers get rewarded. Do punishers get rewarded for their punitive behavior? We investigated this question using a scenario study.

Prisoner’s dilemma AllocatorRecipient Dictator game Flash report of the findings When a punisher was a recipient in a dictator game, Only 33% of our participants wanted to play with a punisher rather than a non-punisher. Punisher’s payoff: 2,964 < Non-punisher’s payoff: 4,655 In a prisoner’s dilemma game, 69 % of our participants wanted to play with a punisher rather than a non-punisher. Punisher’s payoff: 6,346 > Non-punisher’s payoff: 2,500 The answer to the question depends on the type of game. The details of the study follows…

Background Punishment of free-riders is a key to maintain cooperation in n-person dilemmas. (e.g., Yamagishi, 1986 Fehr & Gächter, 2002) However, punishment invokes a second-order social dilemma problem (Yamagishi, 1986). If punishers get rewarded and the benefits surpass the cost of the punitive behavior, the punishment of free- riders can be sustained. However, people do not seem to reward punishers. (Kiyonari & Barclay, 2008)

Outline of this study ►Participants chose either a punisher or a non- punisher as a game partner in those games. The game type is important. ►Punishers were not rewarded by others when they were a recipient in a dictator game. ► Punishers may be rewarded when they play a prisoner’s dilemma game. In addition to these two games, we examined other games using scenarios.

Method Participants: 57 undergraduate students (40 males, 17 females) public goods game third-party punishment game Participants read an initial scenario describing a public goods game or a third-party punishment game (Fehr & Fischbacher, 2006). In each initial scenario, a punitive cooperator and a non-punitive cooperator were depicted. punisher non-punisher non-cooperator Punish non-cooperator -10,000 yen -2,000 yen ※ Punishers paid costs to decrease non-cooperator’s payoff Public goods game Third-party punishment game Participants or Initial scenario ※ We pooled two initial scenario conditions when we analyzed.

Method: partner choice After reading the initial scenario (the public goods game or the third party punishment game), participants read 8 scenarios and were asked to imagine themselves in the player’s role. 1. Prisoner’s dilemma game (PD) 2. Public goods game (PGG) 3. Proposer 4. Responder 5. Allocator 6. Recipient 7. Truster 8. Trustee participants Ultimatum game (UG) Dictator game (DG) Trust game (TG)

Method: partner choice We asked participants whether they would want to choose either a punisher or a non-punisher as a game partner in each game. punisher non-punisher Which person do I want to play this game with…?

Result: partner choice Punishers were chosen more than non-punishers. Punishers were chosen less than non-punishers.

Punishers were less chosen as a game partner than non-punishers. ： Participant ： Punisher In these games, punishers were the recipient of resources. Responder AllocatorRecipient Truster Trustee Group fund Proposer Dictator game Ultimatum game Public goods game Trust game Punishers were not chosen as a recipient of rewards. This result suggests that punishers are not rewarded by others.

Punishers were more chosen as a game partner than non-punishers. Allocator Recipient Truster Trustee ： Participant ： Punisher In these games, punishers were providers of resources. Prisoner’s dilemma Dictator game Trust game Punishers were chosen as resource providers. Punishers were trusted more than were non-punishers.

Further analysis: Evaluation Participants rated their general impression of punishers and non- punishers by comparing the punisher and the non-punisher on 25 impression items. (7 points scales) Which person is more “trustworthy”, “kind”, “friendly” and so on same participants punishernon-punisher Why were punishers chosen as providers? ➔ We analyzed how our participants evaluated punishers and non- punishers.

Further analysis: Evaluation Principle component analysis revealed 4 dimensions of evaluation. Friendliness (α=.79): “want to be friends with,” “feel safe with,” “kind,” “respected by others,” and so on. Justice-seeking (α=.85) : “worthy leader,” “relied on by others,” “justice minded,” “socially desirable character,” “trustworthy,” and so on Harmony seeking (α=.80) : “concerned about own reputation,” “likely to get help from others,” “respects group harmony,” and so on. Cleverness (α=.68) : “clever,” “get along well in society,” and “meddling” (reverse)

Result: Evaluation Punishers were evaluated as more justice-seeking than non-punishers. Punishers were perceived as less friendly and harmony-seeking than non-punishers. Punishers were perceived as less socially clever than non-punishers. Punishers may have been chosen as providers because they were perceived as fairness-seeking. Non-punishers may have been chosen as recipients because they were perceived as friendly and agreeable.

Further analysis: Behavior Participants stated how they and their partner (the punisher or the non-punisher) would behave in each game. We calculated how much punishers and non-punishers would earn, if they and participants actually behaved the way participants had stated. expected payoff We called these calculated earnings the “expected payoff”. punisher non-punisher interact Are there other benefits to punishers?

Result: Behavior Participants chose punishers only when they expected to earn more by doing so. (The only exception was when participants played the public goods game) Games in which a punisher / non-punisher plays Punisher was chosen (%) Participant’s expected payoff from punisher (yen) Participant’s expected payoff from non- punisher (yen) Dictator in Dictator Game 76.89,3517,527 Prisoner’s dilemma game 69.29,3857,946 Trustee in Trust Game 66.09,2328,386 Proposer in Ultimatum Game 58.29,0718,473 Truster in Trust Game 36.48,5099,679 Recipient in Dictator Game ,73212,123 Public Goods Game ,52714,924 Responder in Ultimatum Game ,05411,350 Regression analysis showed that participants’ expected payoff predicted almost completely the proportions of participants who wanted to play with the punisher. Punisher was chosen (%) =  participants’ expected earnings from the punisher  participant’s expected earnings from the non-punisher R 2 =.99

Result: Behavior Games in which a punisher / non-punisher plays Punisher was chosen (%) Dictator in Dictator Game 76.8 Prisoner’s dilemma game 69.2 Trustee in Trust Game 66.0 Proposer in Ultimatum Game 58.2 Truster in Trust Game 36.4 Recipient in Dictator Game 32.7 Public Goods Game 30.9 Responder in Ultimatum Game 27.8 Punisher’s expected payoff per game play (yen) Non-punisher’s expected payoff per game play (yen) 10,64912,473 8,5966,875 9,5188,807 9,8579,771 7,6317,464 8,2687,877 15,12613,344 9,9468,298 Punishers were expected to earn more in all situations except when they play the dictator’s role in the dictator game. ➔ because participants would give the punisher more resources than the non-punisher. Punishers were not exploited when they were a recipient.

Result: Behavior Games in which a punisher / non-punisher plays Punisher was chosen (%) Dictator in Dictator Game 76.8 Prisoner’s dilemma game 69.2 Trustee in Trust Game 66.0 Proposer in Ultimatum Game 58.2 Truster in Trust Game 36.4 Recipient in Dictator Game 32.7 Public Goods Game 30.9 Responder in Ultimatum Game 27.8 Taking into account the probability that participants chose the punisher and the non-punisher as a game partner, punishers would earn more than non-punishers only in games in which they provided resources to the participant. Punisher’s expected payoff per encounter (yen) Non-punisher’s expected payoff per encounter (yen) 7,8042,286 6,3462,500 6,5853,264 5,8554,200 2,9644,873 2,9644,655 4,7369,855 2,7225,796

Summary of findings ■ ■ Punishers were chosen more frequently as providers of resources than were non-punishers because they were perceived as more trustworthy and fair. Acquiring a reputation of being a punisher may pay off in those games. ■ ■ Punishers were chosen less frequently as recipients of resources than were non-punishers. Acquiring a reputation of being a punisher may not pay off when the punisher plays those games.

Summary of findings ■ ■ Punishers’ expected payoff per actual game play was always higher than non-punishers’. ➔ Participants treated punishers better than non-punishers when they were forced to play.

DiscussionImplications:  Punishers are likely to be chosen as game players when trustworthiness and fairness are needed. ➔ Candidate of a leader.  In addition, punishers are not likely to be exploited.

Thank you for your attention.

Game type and the punisher ’ s role in the game % Punisher was chosen Participant ’ s earnings from punisher Participant ’ s earnings from non- punisher Dictator in DG , ,527 PDG player69.29,3857,946 Trustee in TG66.09,2328,386 Proposer in UG58.29,0718,473 Truster in TG36.48,5099,679 7 Recipient in DG32.711,73212,123 PGG player30.916,52714,924 Responder in UG27.810,05411,350

Game type and the punisher’s role in the game % Punis her was chose n Punishe r’s earning s per game play Non- punisher’ s earnings per game play Punisher ’s earnings per encounte r Non- punisher ’s earnings per encount er Participan t’s earnings from punisher Participan t’s earnings from non- punisher Dictator in DG ,64912,4737,8042,2869,3517,527 PDG player 69.28,5966,8756,3462,5009,3857,946 Trustee in TG 66.09,5188,8076,5853,2649,2328,386 Proposer in UG 58.29,8579,7715,8554,2009,0718,473 Truster in TG 36.47,6317,4642,9644,8738,5099,679 Recipient in DG 32.78,2687,8772,9644,65511,73212,123 PGG player ,12613,3444,7369,85516,52714,924 Responder in UG 27.89,9468,2982,7225,79610,05411,350

Game type and the punisher ’ s role in the game % Punish er was chosen Punisher ’ s earnings per game play Non- punisher ’ s earnings per game play Punisher ’ s earnings per encounter Non- punisher ’ s earnings per encounter Participant ’ s earnings from punisher Participant ’ s earnings from non- punisher Dictator in DG ,64912, , ,2869, ,527 PDG player69.28, ,8756,3462,5009,3857,946 Trustee in TG66.09,5188,8076,5853,2649,2328,386 Proposer in UG58.29,8579,7715,8554,2009,0718,473 Truster in TG36.47,6317,4642,9644,8738,5099,679 7 Recipient in DG32.78,2687,8772,9644,65511,73212,123 PGG player30.915,12613,3444,7369, ,52714,924 Responder in UG27.89,9468,2982,7225,79610,05411,350

Game type and the punisher ’ s role in the game % Punish er was chosen Punisher ’ s earnings per game play Non- punisher ’ s earnings per game play Punisher ’ s earnings per encounter Non- punisher ’ s earnings per encounter Participant ’ s earnings from punisher Participant ’ s earnings from non- punisher Dictator in DG ,64912, , ,2869, ,527 PDG player69.28, ,8756,3462,5009,3857,946 Trustee in TG66.09,5188,8076,5853,2649,2328,386 Proposer in UG58.29,8579,7715,8554,2009,0718,473 Truster in TG36.47,6317,4642,9644,8738,5099,679 7 Recipient in DG32.78,2687,8772,9644,65511,73212,123 PGG player30.915,12613,3444,7369, ,52714,924 Responder in UG27.89,9468,2982,7225,79610,05411,350 Per game play: how much the punisher and the non-punisher each is expected to earn in each game when it is played with the participant (columns 2 and 3 in Table 1). Per encounter: We multiplied expected earnings per played game by the expected probability that the game is played with the participant when he had a choice of the punisher and the non- punisher as a game player.

The results of a principal component analysis of 25 impression items Factor1 Factor2Factor3Factor4 “ want to be a friend with ” “ feel safe together ” “ kind ” “ respected by people around ” * “ threatening ” * “ authoritarian ” “ worthy of a leader ” “ relied on by people around ” “ fair ” “ justice minded ” “ socially desirable character ” “ trustworthy ” * “ concerned only about own interest ” (reverse) * Reverse item

The results of a principal component analysis of 25 impression items Factor1 Factor2Factor3Factor4 “ concerned about own reputation ” “ likely to get help from people around ” “ respective of group harmony ” “ concerned about status difference ” “ respective of order within the group ” * “ selfish ” * “ conceited ” * “ want to be number one ” * “ hate losing ” “ clever ” “ get along well in society ” * “ meddling ” * Reverse item

Public goods game condition. The booklet started with a description of a public goods game in which four players―A, B, C and D―decided how much of an endowment of 10,000 yen they would contribute to the “common fund.” The money contributed to the common fund was doubled by the experimenter and was equally allocated to the four players. The scenario then stated that A and B (cooperators) contributed all 10,000 yen to the common fund, whereas C and D (non-cooperators) contributed nothing. As a result, both A and B earned 10,000 yen and C and D earned 20,000 yen in this game. Participants received further description of the game that the four players were provided with an opportunity to monitor another player’s behavior, and to spend 2,000 yen to punish the monitored player. The punished player would be confiscated 10,000 yen by the experimenter. One of the cooperators, Player A (punisher), found out that Player C did not contribute any, and spent 2,000 yen to punish C. The other cooperator, Player B (non- punisher), also found out Player D did not contribute any, but did not spend 2,000 yen to punish D. Player A is a cooperator and punisher and Player B is a cooperator and non-punisher.

Third-party punisher condition. Participants first received a description of a dictator game in which a dictator received 20,000 yen from the experimenter, and was asked to allocate the money between himself and another player, a recipient. Two of the four players, A and B, who played the role of dictator gave their recipient a fair share of 10,000 yen, whereas the other two, C and D, took all of 20,000 yen and gave their recipient nothing. Participants were further informed that the participants were provided with an opportunity to monitor another player’s behavior. Player A found out that Player C took all the money, and spent 2,000 yen to punish C. Player B also found out that Player D took all the money, but did not spend 2,000 yen to punish D.

Prisoner’s Dilemma Game (PD)

Prisoners’ dilemma game situation. Participant was asked to think of a situation in which he/she and either Player A or Player B was each given an endowment of 5,000 yen from the experimenter, and decided whether or not to give the money to the other. When one gives 5,000 yen, the other receives 10,000 yen. Following this description of the game, participants were asked which of the two players, Player A or B, they wanted to play this game with. They were further asked whether or not Player A would give his/her money to them, and whether they themselves would give their money to A. They were also asked the same set of questions concerning Player B.

Fund Punisher Fund Non-punisher Participant Public Goods Game (PGG)

Public goods game situation. Participant would be a player in a four person game in which four players were each given an endowment of 10,000 yen from the experimenter, and decided how much of it to contribute to a “common fund.” The total sum of the money contributed by the four members to the common fund was doubled by the experimenter and equally allocated to the four players. Then, the four players decided whether they would spend 2,000 yen to punish other players who contributed nothing. Participants were asked to choose which group they wanted to participate in, given a choice between a group including Player A or another group including Player B. They were further asked how much Player A would contribute to the common fund, how much they themselves would contribute if they had been a member of A’s group, and how much the other two members would contribute. They were also asked the same set of questions concerning B’s group.

Trust Game (TG) Truster Trustee

Trust game (trustee’s role). Participants were asked to imagine themselves in the role of truster who decided whether they would receive 5,000 yen directly from the experimenter, or let their trustee partner (either Player A or B) freely divide 20,000 yen between the truster and the trustee. Following this description of the game, participants were asked whether they wanted to play this game with Player A or Player B. They were further asked which option (sure 5,000 yen or a share of 20,000 yen) they would choose if Player A was his/her partner, and how much Player A would give to the partner if he/she was given a chance to freely divide the money. They were also asked the same set of questions concerning Player B as a trustee.

Trust game (truster’s role). Either Player A or Player B would decide whether he/she received 5,000 yen directly from the experimenter, or let the participant freely divide 20,000 yen. Participants were asked whether they wanted to play this game with Player A or Player B. They were further asked which option (sure 5,000 yen or a share of 20,000 yen) Player A would choose if A was his/her partner, and how much the participant would give to A if he/she was given a chance to freely divide the money. Participants were also asked the same set of questions concerning Player B as a partner.

Proposer Ultimatum Game (UG) Responder

Ultimatum game (responder’s role). Participant would receive 20,000 yen from the experimenter, and was asked to decide how to divide the money between him/herself and either Player A or Player B. Player A or B had an option to accept the division or reject it. If he/she accepts the division, both the participant and A or B would receive respective shares of the money according to the player’s division. If he/she rejected the division, neither party would receive any money. Participants were asked whether they wanted to play this game with Player A or B. They were further asked how they would divide the money between themselves and Player A, and if Player A would accept or reject their division. They were also asked the same set of questions concerning Player B as a partner.

Ultimatum game (proposer’s role). Either Player A or Player B would receive 20,000 yen from the experimenter, and was asked to decide how to divide the money between him/herself and the participant. The participant had an option to accept the division or reject it. If he/she accepted the division, both the participant and A or B would receive respective shares of the money according to A’s or B’s division. If he/she rejected the division, neither party would receive any money. Participants were asked whether they wanted to play this game with Player A or Player B. They were further asked how Player A would divide the money, and if they would accept or reject Player A’s division. They were also asked the same set of questions concerning Player B as a partner.

Dictator Game (DG) AllocatorRecipient

Dictator game (recipient’s role). The participant would receive 20,000 yen from the experimenter, and is asked to decide how to divide the money between him/herself and either Player A or Player B. Participants were asked whether they wanted to play this game with Player A or Player B. They were further asked how they would divide the money between themselves and Player A. They were also asked the same question concerning Player B as a partner.

Dictator game (dictator’s role). Either Player A or Player B would receive 20,000 yen from the experimenter, and was asked to decide how to divide the money between him/herself and the participant. Participants were asked whether they wanted to play this game with Player A or B. They were further asked how Player A would divide the money between him/herself and the participant. They were also asked the same question concerning Player B as a partner.