垄断的间接社会福利效益分析

The Analysis of Indirect Social Welfare by Monopoly

本文在传统的福利分析模型中加入税收变量 ,同时结合公共产品的社会效益函数 ,通过分析税收这一中间变量对垄断效应的传导 ,推导出垄断造成的间接社会福利效益 ,即从垄断间接外部效应的角度 ,探讨垄断这种市场结构对社会的净福利。在一定条件下 ,本文得出以下的结论 :首先 ,在考虑了垄断间接社会福利效益后 ,垄断造成的福利三角形损失有可能被弥补 ,只要满足一定的条件 ,垄断对社会的净福利效益可能为正。其次 ,税收作为垄断效应传导的中间变量 。

The paper indicates the indirect social welfare by monopoly with the tax as the intermedia through putting the variable of tax and the utility function of public goods into the traditional welfare analysis model . Namely, it discusses the net utility by the indirect effects of monopoly from the angle of external monopolistic effects. Under certain situation, the paper comes to a conclusion as follows: Firstly, the triangle welfare loss can be made up if we take the external monopolistic effects into account. In another word, monopoly can create positive social welfare under certain circumstance. Secondly, as the intermedia to conduct the monopolistic effects, the change of tax contributes extremely to the net utility by the effects of monopoly.