| Profound changes have taken place in the decision-making environment and groups with the development of social economy.With the increase of complexity and uncertainty,as well as the sharp increase of knowledge and information,the traditional decision paradigm of group decision-making has gradually changed to the large group decision-making.Compared with traditional group decision-making,opinion conflicts are more likely to occur in the process of large group decision-making,and it is more difficult to reach consensus.Therefore,how to establish an effective consensus reaching mechanism is the key to the current large group consensus decision-making research.In addition,with the development of the Internet,social media has gradually become a popular tool to support personal communication,which also leads to certain social relations.Social trust relationship is considered to be the basis of communication and interaction among decision makers,and also a key factor to promote consensus.However,some individual trust relationships are difficult to obtain because of the large number of participants in large group decision-making.Therefore,how to solve the consensus problem in large group decision-making with the help of social trust network is worthy of extensive and in-depth research.Based on this,this paper systematically and deeply studies the large group consensus decision-making method based on social trust network,including the lack of trust evaluation model of social trust network,the method of determining the heterogeneous weight of decision makers and subgroups,and the consensus reaching process considering trust relationship and bounded confidence.Finally,a case study on the alternative selection of the old urban reconstruction in the livelihood project is used to highlight the applicability of the proposed method and model.The details are as follows:(1)The evaluation model of the unknown trust degree in the social trust network.Social trust relationship is the basis of communication and interaction among decision makers,and it is also the key factor in achieving consensus.The social trust network with high integrity is helpful to analyze the interaction among decision makers.However,it is difficult for some members to evaluate strangers accurately under the condition of more participants,which leads to the incompleteness of social trust networks.Therefore,a two-stage social trust network completeness analysis method is developed to explore the potential trust relationships,including the trust propagation mechanism based on trust utility,the trust aggregation method based on reliability and the trust modification model based on recency effect.The relationship between the parameters in the model is discussed with a collection of simulation experiments.On the basis of comparison with the existing studies,the usefulness and superiority of the proposed methods are analyzed and demonstrated in detail.(2)Method of determining heterogeneous weight for decision makers and subgroups.The determination of the weights for decision makers and subgroups is studied considering the premise of social trust network.Firstly,the method of determining the decision-maker’s heterogeneous weight is proposed,considering the social influence and distinguishing degree of opinion are taken as the basis of evaluating decision makers’ importance.To alleviate the complexity of the large group decision-making,a large group clustering framework based on opinion evolution model is proposed,which divides decision-makers into several subgroups.Then,a method for determining subgroups’ heterogeneous weight is proposed considering subgroups’ size and cohesion.The Uninorm operator is used to combine the heterogeneous weights,where the parameter is determined and discussed with the help of simulation experiments.Finally,the effectiveness of the developed methods is substantiated by a collection of simulation experiments,and the innovation and superiority of which are further highlighted by comparing with related studies.(3)The consensus-reaching process based on trust relationship.Firstly,the influence of the selection of integration operator on the initial consensus level of subgroups is analyzed by simulation experiments.Combined with the trust relationship between subgroups,a consensus-reaching process based on trust relationship and bounded confidence is proposed,which mainly includes the bounded confidence determination method and feedback adjustment method basedthe on the trust relationship.Based on the above,a consensus optimization model with subgroup as the main decision-making subject is constructed for the purpose of minimum adjustment.Finally,based on a series of simulation experiments,the validity and superiority of the proposed method and model are analyzed and demonstrated in detail.(4)The application of large group consensus decision-making method for old urban renewal projects.In view of the large group consensus decision-making for the old urban reconstruction project under the background of social trust network,a large group consensus decision-making method consideding the social trust network is developed to deal with the issue of alternatives selection for the old urban reconstruction project,including the evaluation model of lack of trust in social trust network,determination method of heterogeneous weight for decision makers and subgroups,and consensus reaching process based on trust relationship and bounded confidence.The corresponding management enlightenment is summarized through analysis and discussion to provide method reference and guidelines for solving some livelihood project decision-making problems. |
