Three-Way Group Decision Based on Social Network

In a real-world group decision-making scenario, there are different trust relationships among decision makers, which forms a social trust network [17]. Although the existing researches of consensus reaching process investigate adjustment mechanisms, they rarely consider the effects of the externality of social trust, e.g., [8]. Under the influence of the externality, the adjustment of a decision maker who is persuaded by the moderator can influence other decision makers to accordingly adjust the evaluations in the consensus reaching process. It is significance to make full use of the externality effect to improve the efficiency of collective wisdom. In light of the results of Ref. [14], a mixed 0-1 linear optimization consensus model based on the loss functions of three-way group decision is firstly proposed considering the externality phenomenon of group decision making. In the model, to reflect the situation of influence of decision makers during the consensus reaching process caused by the externality, the weights of decision makers according the trust in-degree and trust out-degree are calculated. By utilizing the relationships of loss functions, we further discuss a two-stage mixed 0-1 linear optimization consensus model for the determination of loss function of three-way decision. Then, based on the results of Ref. [14], we construct a complete decision procedure for three-way group decision via Bayesian decision procedure.