Information Aggregation and Positive Self Image

本文提出了两种新的决策模型和信息处理模型。这些模型的数学性质将引起经济理论家的兴趣。此外，由此产生的模型将有助于组织令人困惑的观察结果，并提出理解和处理行为偏见的新方法。一个模型研究了群体极化现象：群体倾向于做出更极端的决定，而群体中的个人在孤立的情况下会做出更极端的决定。关于这一主题的文献经常将群体极化与非理性联系起来，但它并没有提供一个理性行为的模型。本研究建立了一个基准模型。该模型使我们能够调查，在允许共享信息和选择共识选择的情况下，个人单独做出的决定与同一个人做出的决定之间，何时存在系统关系。确定了群体极化符合理性模型的条件。第二个模型解释了人们倾向于拥有积极的自我形象的发现：当与他人比较时，人们高估了自己的优秀品质。该模型假设人们知道自己的品质，但观察到别人的品质有误差，这可能是有偏见的。该模型能够描述目前主流的积极自我形象动机模型所不能解释的经验规律。例如，该模型预测在某些情况下存在消极的自我想象，并暗示当成功容易获得时，会有更多的积极的自我形象。该模型做出了可检验的预测，使其区别于其他模型。更广泛的影响：认识到决策者在做出选择的方式中表现出系统性的偏见，对经济制度的设计具有启示意义。积极的自我形象与过度冒险和糟糕的生命周期规划（无论是职业选择还是储蓄行为）有关。本研究对积极自我形象的解释表明，提供更多信息的自然干预会减少决策偏差。群体极化的现象使得一些法律学者提出对陪审制度进行改革，特别是对陪审在判定惩罚性赔偿中的作用进行改革。如果没有本研究中开发的模型，人们就无法评估这些提议的成本和收益。

Two novel models of decision making and information processing are developed in this study. The mathematical properties of these models will be of interest to economic theorists. In addition, the resulting models will help to organize puzzling observations and suggest new ways to understand and deal with behavioral biases.One model examines the group polarization phenomenon: the tendency for groups to make more extreme decisions that the individuals within the group would make in isolation. The literature on this topic often associates group polarization with irrationality, but it does not supply a model of what rational behavior is. This study develops a benchmark model. The model makes it possible to investigate when there is a systematic relationship between the decisions individual would make in isolation and the decisions the same individuals would make it permitted to share information and select a consensus choice. The conditions under which group polarization is consistent with the rational model are also determined.The second model accounts for the finding that people tend to have positive self image: when comparing themselves to others, individuals overestimate their good qualities. The model assumes that people know their own quality, but observe the quality of others with an error, which may be biased due. The model is capable of describing empirical regularities that are not explained by the leading motivational models of positive self image. For example, the model predicts the existence of negative self imagine under some circumstance and implies that there will be more positive self image when success is easy to obtain. The model makes testable predictions that distinguish it from alternative models.Broader Impacts: Recognition that decision makers exhibit systematic biases in the way that they make choices has implications for the design of economic institutions. Positive self image has been associated with excessive risk taking and poor life-cycle planning (either in career choice or savings behavior). The explanation for positive self image offered in this study suggests that a natural intervention, providing more information, will reduce decision making bias. The phenomenon of group polarization has led some legal scholars to propose reforms to the jury system, especially with respect to the jury's role in assigning punitive damages. One cannot evaluate the cost and benefits of these proposals without a model like the one developed in this study.