市场势力、基础设施投入与银行卡支付平台交易量

摘要

Both direct and indirect effects are involved during the process of market power determining trading volume,but the latter is often overlooked. The infrastructure investment behavior of bankcard payment platforms bridges its market power and trading volume and is an important source of indirect effects. This paper employs the quarterly operating data of four bankcard payment platforms ranging from 2006 to 2013 to empiri-cally investigate the indirect role of infrastructure on the relationship between market power and trading vol-ume. Taking endogeneity issues into account,the results of benchmark model show that the infrastructure in-vestment serves as a (completely)mediator rather than a moderator. To be more precise,once the role of in-frastructure investment is taken into consideration,the direct effect of market power on the trading volume of payment platforms is no longer significant,and market power only indirectly affect the trading volume of pay-ment platforms through the "pipeline"function of infrastructure investment. Moreover,it's found that infra-structure investment works as a moderated mediator. To be detail,the mediating effect caused by infrastructure investment is obviously heterogeneous and moderated by the ownership of bankcard payment platform. Com-plete mediating effect is significant for open bankcard payment platforms while partial mediating effect is signif-icant for close-ended bankcard payment platforms. The policy implication lies in that the China UnionPay must commit itself to creating open and shared payment ecology for its member institutions. Only by co-con-structing and revitalizing infrastructures with members can China UnionPay resolve the diverging threats of trading volume in the post-CUP era.%市场势力决定交易量的传导过程包含直接效应和间接效应,但后者常被忽视.银行卡支付平台的基础设施投入使其市场势力与交易量相衔接,是形成间接效应的重要来源.基于寡头银行卡支付平台2006-2013年的季度运行数据,在考虑内生性问题的前提下,重点分析基础设施投入作为中间变量在市场势力决定支付平台交易量过程中所产生的间接效应.构建和运用基准模型研究的结果表明:基础设施投入在市场势力决定支付平台交易量过程中发挥了(完全)中介作用而非调节作用.即考虑到基础设施投入的作用后,市场势力对支付平台交易量的直接影响不再显著,市场势力只通过基础设施投入的"管道"功能间接影响支付平台的交易量.进一步分析发现,基础设施投入是一项被调节的中介变量,其间接效应(中介作用)受支付平台所有制的调节而表现出明显的异质性:在开放式支付平台情境下呈现出显著的完全中介效应,在封闭式支付平台场景下则展现出显著的部分中介效应.政策启示是,中国银联宜致力于为成员机构营造基础设施开放共享的支付生态,共建和盘活并举,化解后银联时代交易量分流的威胁.