We investigate whether diversification affects bank risk taking in the U.S. banking industry, and whether this relation is partially explained by agency theory. Our results show that U.S. banks with a relatively high share of noninterest income become riskier when moving toward non‐interest‐income‐generating activities, especially activities from investment banking, proprietary trading, and so on. Diversification not only affects conditional average risk, but also the dispersion of risk. Moreover, diversified banks that received assistance from the Troubled Asset Relief Program (TARP) become riskier than diversified nonrecipients after TARP capital injections. Our main findings are robust to a battery of robustness tests. The results are partially explained under agency frameworks related to poor corporate governance.

中文翻译：

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活动策略，代理商问题和银行风险

我们研究多元化是否会影响美国银行业的银行风险承担，以及这种关系是否由代理理论部分解释。我们的结果表明，非利息收入份额相对较高的美国银行在转向非利息收入活动（尤其是投资银行业务，自营交易等活动）时会变得更有风险。多元化不仅影响有条件的平均风险，而且还影响风险的分散。此外，在不良资产救助计划（TARP）的支持下，接受多元化资产救助计划（TARP）援助的多元化银行比多元化非受赠人注入风险更高。我们的主要发现对一系列的稳健性测试是可靠的。在与公司治理不佳相关的机构框架下，对结果进行了部分解释。