Samid et al[3] 2009 esa innsbruck talk


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  • In this experiment 24 Participant played a Public Goods game In groups of 4 players. In the game they can contribute 0 to 20 MUs which are multiplied by 1.6 and divided among all 4 players. After each trial groups were re-matched so that each 2 players do not shared the same group more the once. This procedure called “The Total Stranger” and as a result of this procedure punishing other group members is completely altruistic. When punishing one pays for causing the other to cooperate even so he cannot benefit from the other’s cooperation.
  • . It is in the best interest of everyone that the defector be punished, but each individual is better off not to pay the cost of punishing. Put differently: Individuals who contribute, but do not punish, are better off than the punishers. 2) Estes, W. K. (1944). An experimental study of punishment. Psychological Monographs, 57(No. 263).
  • In comparison with the cross-cultural survey, the punishing behavior at Haifa is more like Istanbul than like Muscat. At Haifa we have High level of Anti-Social Punishment but a much higher levels of Pro-Social Punishment.
  • When going into more details we can check the efficiency of punishment by plotting the punishment expenditure as a function of the deviation of the contribution of the punished group member from the mean contribution of the other members. We can see that for free-riders (negative deviations) both Haifa and Zurich show an efficiency slope , with a steeper slope for Zurich. On the other hand, for positive deviations we see a negative slope at Zurich and a positive slop at Haifa (the difference between is significant ). For Zurich we can say that the more one cooperates the less likely that he will be punished. For Haifa we can say that while free-riders are likely to be punished cooperation above group average will not reduce the likelihood of punishment.
  • In order see the punishing player’s behavior we plot the deviations at individual levels. Here we see the deviation between the contributions of each pair of players. According to this deviations we can see to whom players allocate their punishment relative to their on contribution. At the negative deviation of the free-riders punishment, the slops look the same as in the previous plot, participants allot more punishment to those who exploit their cooperation. But at the positive deviation we see that while at Haifa Anti-social punishment is indifferent of the deviation at Zurich Anti-social punishers would allocate more punishment to those who highly exceed the punishing player’s contribution. Meaning that low contributing players are most likely to punish the most cooperative players in the group. At Herrmann et al. (2008) cross-cultural experiment anti-social punishment was associated with people who do not accept punishment and seek revenge, I this experiment one cannot revenge because you play only once with each participant. We believe that in view of a large deviation some low contributors feel lowly by the much higher contribution and punish the cooperator in order to lower his contribution to what they feel is an acceptable cooperative norm.
  • Following a control condition the option of sending messages can increase cooperation level. In the second graph we see that messages maintain cooperation at initial level but when they are ruled out cooperation collapses. Therefore the hypothesis that messages will have long lasting educational value is rejected.
  • In the first sequence punishment did not differ from the control while messages show a significantly higher cooperation level than punishment and control. In the second sequence messages outperform the two control conditions {but they do not reach higher cooperation than the punishment condition at the first sequence. }
  • Here we see that the messages Condition is the most profitable one followed by the standard PG game – control condition. Notice that the control condition in Haifa did not differ from Zurich. Punishment is the least profitable condition although it shows some improvement along the six trials. ( we may expect profitability in longer repeated games). Not surprisingly, punishment at Haifa was the least profitable condition, due to a low cooperation level combined with a high punishment level.
  • Messages were sent about 2300 times, which constitute 53% of the optional interactions. Punishment was used on 34% of the optional interactions. We had six judges rate the messages as positive negative or neutral criticisms and for suggestions to increase or decrease contributions. All suggestions were considered as negative reinforcements unless it contained positive criticism. We can see that messages where most frequently used for negative reinforcement, and out of all interactions, negative reinforcements are almost one third which is as frequent as punishment in Haifa and Zurich.
  • Messages enhance cooperation, but unlike punishment they do not make free-riding non-beneficial. Consequently, in an evolutionary process they cannot immune societies against free-riders. It is probable that a combination of messages and punishment can enhance cooperation in an efficient and low cost manner, since punishment could then be used only against persistent defectors.
  • בתרשים רואים שככל שהתרומה של שחקן היתה יותר נמוכה מהממוצע של קבוצתו כך העונש קיבל היה יותר גבוה . כלומר הענישה פגעה קשות באפשרות להרויח מעריקה . דבר נוסף שבולט כאן הוא שגם בצעד השישי ( האחרון ) שיעור ענישת העורקים לא פחת .
  • המשמעות באמצעות ענישה אלטרואיסטית רמת התרומות אמנם עולה מאוד אך אין כאן למידה המשמרת את עצמה וכאשר מונעים את האפשרות להעניש העורקים חוזרים לערוק ולאחר 6 צעדים מצטרפים אליהם רוב השחקנים . אם נסתכל על העונש שקיבלו השחקנים נקבל את הטבלה הזאת :
  • Samid et al[3] 2009 esa innsbruck talk

    1. 1. Costless Messages Outperform Altruistic Punishment Yuval Samid*, Ramzi Suleiman † , Tali Rainfeld-Rachlevsky † & Amir Hayek * Independent Researcher, 16 Shazar St., Haifa, Israel. † University of Haifa, Department of Psychology, Mount Carmel, Haifa, Israel. ‡ MCE-Systems, 51 Hamasger St, Tel-Aviv, Israel. We thank Keren Guz, Maayan Armelin, Fadi Farraj, Dina Baransi, Tamar Karanik and Maital Erlichman for their help in running the experiments Paper presented at the ESA Regional Meeting Europe 2009 , Innsbruck, Austria, SEPTEMBER 17-20
    2. 2. Studies on human cooperation show that, unlike other creatures, cooperation is frequent among genetically unrelated strangers, in non-repeated interactions and when gains from reputation are small or absent. Cooperation in these situations can be explained by altruistic punishment (Fehr & Gächter, 2002).
    3. 3. <ul><li>Previous research have demonstrated that: </li></ul><ul><li>Individuals engage in altruistic punishment, although it is costly. </li></ul><ul><li>Negative emotions towards defectors are the proximate mechanism behind altruistic punishment. </li></ul><ul><li>Altruistic punishment evolves even in large groups engaged in one-time, anonymous interactions. </li></ul>
    4. 4. Cooperation flourishes if altruistic punishment is possible, and breaks down if it is ruled out. Source: Fehr & G ä chter, 2002
    5. 5. Punishment has some serious drawbacks: 1) It is costly to punishers, hence it creates a second-order social dilemma (Yamagishi, 1987; Hauert et al., Science, 2007). 2) It bears no educational value. When punishment is terminated, the achieved cooperation is extinguished (Estes, 1944). 3) It undermines trust and confidence in voluntary cooperation (Mulder et. al., 2006)
    6. 6. In view of the disadvantages of punishment, we replaced the option of punishing other group members with the option of sending them costless, freely written messages.
    7. 7. <ul><li>Possible advantages of messages over punishment : </li></ul><ul><li>Since messages are costless, they can yield higher profits than the payoffs obtained by punishment. </li></ul><ul><li>While punishment can only serve as negative reinforcement, messages can be used as both positive and negative reinforcements. </li></ul><ul><li>Messages can bear an additional informative value, which might be beneficial for organizing cooperation. </li></ul><ul><li>Messages have an educational value, therefore their long-term effect on cooperation may be more pronounced than punishment. </li></ul>
    8. 8. <ul><li>Hypothesis: </li></ul><ul><li>Messages will be frequently used and will be addressed to both defectors ( negative verbal reinforcement ) and cooperators ( positive verbal reinforcement ). </li></ul><ul><li>The use of messages will enhance cooperation, or at least maintain it at its initial level. </li></ul><ul><li>When the option for sending messages is ruled out, cooperation will not brake down (educational effect). </li></ul><ul><li>Sending messages could yield higher profits than punishment. </li></ul>
    9. 9. First we replicated Fehr & Gächter’s (2002) Altruistic Punishment experiment. But punishment was not as effective. The weak punishment effect is attributed to cultural differences in punishing behavior (Herrmann, Thöni, Gächter, Science 2008, )
    10. 10. The effect of cultural differences in punishing behavior on cooperation in a public goods dilemma (Herrmann, Thöni, Gächter, Science , 2008) . For the punishment condition at Haifa, the average contribution was 9.3 (MU) , which puts us between Istanbul and Muscat .
    11. 11. Without punishment the cultural differences are less evident.
    12. 12. This cultural differences can be seen in the amount of punishment allocated to cooperators (also called Anti-social punishment ) .
    13. 13. <ul><li>In comparison with Zurich (Fehr & Gächter, 2002) , punishment expenditure was significantly higher at Haifa, 2.95 points per trial at Haifa , compared to 2.07 at Zurich ( Z = -2.51, P = 0.006, two-tailed Wilcoxon Two-Sample Test). </li></ul><ul><li>When comparing the allocation of punishment between free-riders and cooperators, we observe that higher levels of anti-social punishment were allotted in Haifa ( χ 2 (1) = 3.59, P = 0.0582, GEE Analysis) . </li></ul>
    14. 14. This cultural differences in Anti-social punishment
    15. 15. Expenditure on punishment as a function of the deviation of the contribution of the punished group member from the mean contribution of the other group members. Negative deviations = Free-riders – both slopes and difference between slopes are significant Positive deviations = Cooperators – difference between slopes is significant
    16. 16. Punishing behavior: Mean punishment expenditures for a given deviation from the punisher’s contribution.
    17. 17. Results of the message condition
    18. 18. With messages Without messages Mean contribution in the Message and Control condition Without messages With messages
    19. 19. Comparison of punishment , messages and control conditions
    20. 20. Comparison of the net profits in all conditions at Haifa and Zurich
    21. 21. Frequencies of messages and punishment utilization.
    22. 22. Examples of “anti-social” messages <ul><li>Well done! But in the end you will loose a lot of money </li></ul><ul><li>Ooopss, try to be smart not righteous </li></ul><ul><li>You even don’t know who I am. Start living for yourself, and not for others </li></ul><ul><li>15 is agreed by all (sent to participants who contributed 20) </li></ul><ul><li>Optimism is nice! </li></ul>
    23. 23. 1. Messages will be frequently used and will be addressed to both defectors and cooperators. Hypothesis: 2. The use of messages will enhance cooperation, or at least maintain it at its initial level. 4. Even if less effective than punishment, sending messages could yield higher profits than punishment. 3. When the option for sending messages is ruled out, cooperation will not brake down (educational effect). Confirmed Confirmed Rejected Confirmed
    24. 24. Summary and Main Conclusions <ul><li>Punishment in Haifa was not effective. </li></ul>2. Verbal messages in Haifa outperformed altruistic punishment. 4. A Combination of punishment and messages could prove cost-efficient. 3. It remains to investigate whether verbal messages outperform altruistic punishment in cultures with documented punishment efficacy.
    25. 25. Thank you for listening
    26. 26. מידת הענישה האנטי - סוציאלית ( ענישת תורמים ) יכולה להסביר את חוסר ההשפעה של ענישה בחברות שונות ( Herrmann, Thöni, Gächter, 2008 Science )
    27. 28. (Fehr & Gachter, 2002, Nature )