社会资本外部性的经济分析——以信任关系为例

以往理论研究与经验研究均指出社会资本具有正面的效应,但对这种效应是怎样取得的并无共识.我们尝试建立一个不完全信息动态博弈模型,说明社会资本-信任如何产生正的外部性,亦即产生超出个体理性计算之外的利益.我们的分析得出这样的结论,在一个多人互动的环境中,能否达到彼此合作或彼此信任,虽然会受到欺骗者所遭到的惩罚与欺骗利益多少的影响,但主要受到所处环境中具有社会资本者人数比例的影响.因此,可以说社会资本具有正的网络外部性,信任者人数越多,信任者所享受到的利益越大.

An Economics Analysis on Social Capital Externalities——Exampled by Trust

Current literatures of theoretical and empirical studies show positive effect of social capital. However, disputes still remain on how this positive effect is attained. We try to establish a dynamic game model with incomplete information to show how the positive effect is produced by social capital-trust. We conclude that in multi-part interaction, whether cooperation or trust can be achieved is primarily determined the number of the people involved in the game. Thus, social capital has positive network externalities, the greater number of people are endowed trust, the greater benefit enjoyed by trustees.