最优银行集中度之谜

The Myth of the Optimal Bank Concentration

本文通过对89组跨国数据的实证分析,系统研究了银行集中度和银行体系稳定性之间的关系。实证结果表明,银行集中度和银行稳定性之间的关系并不是过往文献所集中讨论的简单线性关系,而是存在一个最优的银行集中度区间(0.6,0.8],这一区间恰好位于样本均值附近,并向样本均值收敛;而当一国的银行集中度水平处于(0.8,0.9]时,银行体系的稳定性最低,极易发生银行危机。进一步的分析表明,在最优的银行集中度区间内,银行业的产业结构能较好地在适度竞争和盈利之间获得平衡,而隐藏在"最优银行集中度之谜"背后的机制极有可能是"优胜劣汰"这一自然法则在社会经济领域的再现。

Based on 89 groups of cross-country data,this paper empirically studies the relationship between bank concentration and banking stability.The results show that the relationship between bank concentration and banking stability is not simply linear correlation indicated by most former researches.On the contrary,there exists an optimal bank concentration interval,(0.6,0.8],which clusters around and converges to the sample mean;when the bank concentration falls in the interval of(0.8,0.9],the banking system has the worst stability and banking crisis easily breaks out.The further analysis reveals that in the optimal bank concentration interval,the banking industry structure can achieve the best balance between proper competition and profitability,which leads us to conjecture that the mechanism behind the"myth of optimal bank concentration"may be the representation of the natural principle of"survival of the fittest"in the social and economic area.