Gauging the efficiency of bank consolidation during a merger wave
指出银行合并浪潮可能带来效率提升，但传统面板或横截面分析难以发现，因为合并浪潮给事件研究和绩效比较带来计量陷阱。通过九个案例研究，作者建议更多依赖跨体制比较来衡量合并收益。
By many measures, bank consolidation waves, historically and currently, produce substantial efficiency gains associated with reduced operating costs, enhanced diversification, and the enrichment of bank-customer relationships. These gains may be hard to discover in panel or cross-sectional analyses of individual banks because merger waves pose special econometric pitfalls for event studies of stock returns and bank performance comparisons. We review these problems and summarize lessons from nine case studies of individual merger transactions which offer qualitative evidence that potential econometric pitfalls can be important. Those conclusions suggest placing greater weight on cross-regime comparisons for measuring gains during bank merger waves.