Experimental psychological studies of the inductibility of responses into prosperity state in social interaction situation

“囚徒困境”是指在实验博弈情境中，每个参与者的“个人理性”动机与“群体理性”动机之间发生社会冲突的一种典型心理情境。在相同的收益矩阵反复呈现给双方的情况下，双方往往会选择非合作方案，从而陷入囚徒困境中的“互贫细胞”。参与者如何从这个格子中解脱出来一直是囚徒困境研究的重要课题之一。这两项实验研究通过关注以下方面来寻找诱导玩家反应进入繁荣细胞的具体手段：一是“以牙还牙”策略的影响，二是玩家认知形式对基于“复合分解博弈”的情境所涉及的收益结构的影响。主要研究结果如下：在实验1(1)中，有几种关于针锋相对的策略，而最佳策略取决于玩家作为情境“控制者”的目的。2)为了使双方的联合收益最大化，“同时针锋相对”是最可调整的策略。(3)为了实现个人利益最大化，“以牙还牙，双重报复”是一种可调节策略。4)对于最易调整的策略，复仇的放大力在实验中没有确定。在实验2中，1)“复合分解游戏”并不能有效地诱导玩家对繁荣细胞的反应。2)对指示其他玩家情况结构的信息的控制非常有效，能够引导他们对繁荣细胞做出反应。拖延对背叛者的报复是无效的。

"Prisoner's dilemma" means a typical psychological situation involving social conflicts between the motives of the "individual rationality" and the "group rationality" for each player in the experimental game situations. In the situation where the same payoff matrix is repeatedly represented to both the two players, they used to select the non-cooperative alternatives to fall into the "mutual poverty cell" in the prisoner's dilemma. How the players can extricate from this cell has been one of the important subjects in the prisoner's dilemma studies. The two experimental studies were performed to find the concrete means to induce the player's responses into the prosperity cell by focussing to the following aspects: first, the effects of "tit-for-tat" strategies, and second, the effects of the player's cognitive form for the payoff structure which was involved in the situation based upon the "composite decomposed games". The main findings in them were as follows.In the Experiment I, 1) There were several kinds of strategies concerning the tit-for-tat, and the optimum strategy depended upon the purpose of the player as a "controller" for the situation. 2) For maximizing the joint gain between the two players, the "simultaneous tit-for-tat" was the most adjustable strategy. 3) For maximizing the individual gain, the "tit-for-tat with double revenge" was ajustable strategy. 4) The magnifying power of the revenge for the most adjustable strategy was not decided in the experiment. In the Experiment II, 1) The "composite decomposed games" were not so effective to induce the player's responses into the prosperity cell as they were. 2) The control of the information indicating the structure of situation for the other player was so effective to induce his responses into the prosperity cell. 3) The delay of revenge for the betrayer was not effective.