银行贷款市场势力与风险承担——基于规模修正Lerner指数与传统Lerner指数的对比检验

Bank Loan Market Power and Risk-taking——Based on the Comparison Tests of A Scale-corrected Lerner Index and Traditional Lerner Index

本文选取我国91家商业银行2007-2018年的微观数据,检验规模经济对银行业贷款市场势力的影响。检验结果表明,67.57%的样本银行处于规模经济范围,证实有必要构建规模修正的Lerner指数。在此基础上,本文通过规模修正Lerner指数和传统Lerner指数,研究贷款市场势力对银行风险的影响。研究发现,商业银行贷款市场势力与风险之间存在倒U型非线性关系,但规模修正Lerner指数对银行风险的影响要小于传统Lerner指数;此外,两类Lerner指数的实证检验还显示,目前我国银行已处于“竞争-脆弱”区域,应强化市场准入限制,推进中小银行合并重组,预防银行间的恶性竞争。

This paper uses the micro data of 91 banks in China from 2007 to 2018 to test the impacts of scale economy on the bank loan market power.It is found that 67.57%of the sample banks are within the scope of economies of scale.This confirms the necessity to propose a scale-corrected Lerner index.Furthermore,we study the relationship between the loan market power and bank risk by measuring the scale-corrected Lerner index and the traditional Lerner index.The empirical results show that there is an inverted U-shaped nonlinear relationship between banks'loan market power and risk.However,the scale-corrected Lerner index has less impact on bank risk than the traditional Lerner index.In addition,the empirical tests of the two types of Lerner index both show that banks are currently in the"competitive-fragile"region.Regulatory authorities should strengthen entry restrictions and promote the merger and reorganization of small and medium-sized banks to prevent cutthroat competition.