社会网络视角下允许弃权的群决策权力分布

Power analysis of voting games with abstention based on social networks

针对群体决策的权力分布问题,考虑决策规则与网络效应的双重影响,研究社会网络视角下权力的分析方法.通过分析社会网络的结构、测度节点间的影响程度构建群体的影响网络,以影响网络为基础对允许弃权的Banzhaf指数进行拓展,提出网络决策权力的概念及测定方法,并对其性质及影响因素进行分析.结果表明:处于网络中心的个体,会因拥有更多"规则"以外的权力而成为关键决策者;而"规则权力"较高的个体,可能会因处于边缘位置而成为决策中的"弱者".所提出的决策权力考虑了决策个体对结果的直接及间接影响,并提供一种准确反映决策成员贡献程度、识别关键决策者的方法.

This paper proposes a novel power index considering the dual influence of voting rules and social network effect.We analyzed the influence of the change of voter’s viewpoint on voting result based on the influence network which is designed by constructing the social network of decision group and measuring the degree of influence between nodes.The ability of voters to achieve their own decision purpose by influencing others’behavior is defined as the network power,and a network power measure method is proposed by extending the power index of Banzhaf.The properties and influencing factors of the network power index,and its difference from Banzhaf power and network centrality are analyzed.Results show that the individual at the center of the social network may become the key voter because of having more power outside the’rule power’,and a voter with higher’rule power’may become a weak power person because of being on the edge of a group.The proposed power takes into account the direct and indirect effects of voters,which provides a method to accurately identify key voters.