市场结构、经济福利与平台经济反垄断

Market Structure,Social Welfare and Platform Anti-trust

市场结构与经济福利是反垄断政策的重点,现有研究在平台经济的相关市场划分、市场势力界定等方面取得了一定进展,但是尚缺乏从福利角度对平台经济反垄断问题进行系统的分析。本文拓展了阿姆斯特朗的平台经济模型,对比了不同市场结构下的经济福利。研究得出,竞争虽然可以降低平台的溢价能力,但竞争效果受到用户黏性等因素的限制,同时,竞争带来的交叉外部性损失也会对社会福利造成负面影响。在相对集中的市场结构下,如果能有效控制溢价行为,则能够实现社会福利的优化。因此,平台经济反垄断不宜过于偏重市场结构,关键在于对平台的溢价和垄断行为进行监管。平台经济反垄断政策的实施,应该加强经济分析与行为分析,有效保护消费者权益并促进社会经济效率。

Market structure and social welfare are the focus of anti-trust policy.The existing research paid more attention to the determining of market structure,while the study on how the change of market structure will influence social welfare is still lacking.Based on Armstrong's work,a new platform model is established that is able to analyze and compare the social welfare under different market structures.The results show that although a decentralized market structure and competition can reduce the platform's ability to charge monopoly price,the effect of the competition is limited by factors like user stickiness and cross externalities.At the same time,the cross externality loss caused by the decentralized market structure also has a negative impact on social welfare.Under the simultaneous effect of these two factors,the decentralized market structure and competition will decrease social welfare,not increase.As a result,a structuralist antitrust system is not applicable in the platform economy.Under a centralized market structure,if the government can effectively control the monopoly power of the platform,such as banning monopoly acts and reducing platform prices,the optimization of social welfare can be realized.Therefore,the anti-trust policy of the platform economy should not focus too much on the market structure,but on improving social welfare by supervising the behavior and price of platforms.