Study On The Group Polarization Model Considering Decision Maker’s Psychological Behavior

Desicion making sience has been developing rapidly in recent years. Its research of both theory and application are hotspots of Economics area, mathmatics area and management area. From decision making in narrow sence to board sence, From rational decision making to behavial decision making,From single objective decison to multi-objective decision making, From certainty to uncertainty, From simple method to complex method, Desicion making science is developing its own theory and method system.Group decison making is a interdisciplinary research of mathmatics, Politics,Economics,social psychology.behavial theory, management sicen and decision making theory.Because the demand for knowlege of multy-area and benefits of many sides.the Group decison theory and method has a growing importance.The troditional Group decison making theory is based on the hypothesis of complete rationality and complete self-interest. Its research emphasis on how to design the Group decision making procedure and method and developing supporting system, so as to have the best result.However, with the development of behavior sience, there are many Group behavior characteristics like Group polariztion, Group think that have been found.among them the Group polarizaiton phenomenon draw great attention because Its Universaility and significance.This thesis is trying to design an Group decision making model under the condition of Group polariztion.the content of this paper includs.(1)Give a formal description of psychic mechanism of decision making in Group Based on the current research. The main difference between the mechanism of decision making in Individual context and in Group context is except the utility brought by the problem its self, the individual in group is also being influenced by the other members of the Group. The influence can be defined as a concrete value of the decision which is expected by most of other members. When the decision value of the individual is close to the expecting value of the Group, the individual will receive the recognition of the group. If the decision value of the individual is far from the expecting value of the group. The individual shall be ostracized by the group. The individual make its decision in the group with the consideration of both the problem utility and the psychic utility of the group pressure.(2)Build a refined polarization model based on the psychic mechanism of decision making in group. The traditional Group decision making models do not consider the mutual influence of the group members, so they are unable to explain the Group phenomenon. This thesis adds the utility of group pressure into the traditional utility function. Making the optimum value is decided by the utility of both the problem itself and the group pressure. Then a line function and a non-line function of the group pressure is given. The meaning and value of the attributes in the model are discussed, and the extremism of the function is also discussed. The model putting forward in this thesis is a meaningful development of the traditional models.(3)Explore the possible application of the refined polarization model. Firstly, introduce the two classical functions of the group preference and point out its shortcomings. Then a refined new presence of the group preference based on the model of this thesis is given. Because the group preference is a basic and important concept of the whole group decision making theory, the improvement of its function will show great importance in the further work.The research work of this thesis enriches the research on the mechanism of group polarization, which is the psychic mechanism of decision making in group. And also give a new kind of polarization model. To incorporate the mutual influence of group members in the decision making model. This thesis gives a meaningful trial and exploration.