We propose a new test to evaluate the impact of horizontal mergers on competition in the banking industry. The test is designed to be applied ex ante to potential mergers while being parsimonious in terms of data, as it only uses information on branches in local markets. The test is a counterfactual exercise based on a two‐stage model where banks compete in branching and interest rates and requires comparing the estimated degree of competition in the status quo, where branching networks by banks are those actually observed, with a counterfactual scenario, where the branching network of the new entity is the sum of the branches of the banks involved in the horizontal merger. The statistical difference between the two estimated measures of competition quantifies the impact of the merger. We apply our test to French and Italian mergers.

中文翻译：

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合并对银行竞争影响的检验

我们提出了一项新的测试，以评估横向合并对银行业竞争的影响。该测试旨在事前应用于潜在的合并，同时在数据方面非常简单，因为它仅使用本地市场分支机构的信息。该测试是基于两阶段模型的反事实演练，在该模型中，银行在分支机构和利率方面竞争，并要求将估计的现状竞争程度与实际情况进行比较，在这种情况下，银行的分支机构网络是实际观察到的竞争程度，其中新实体的分支机构网络是参与横向合并的银行分支机构的总和。两种估计的竞争衡量方法之间的统计差异量化了合并的影响。我们将测试应用于法国和意大利的合并。