Investigating a unique large data set, we find that automobile insurance policyholders are more likely to encounter accidents during the last month of the insurance policy term than during any other month. Our interpretation is that this effect is driven by the sunk cost fallacy held by policyholders, which exacerbates their moral hazard. The explanation is that in the last month, policyholders may become concerned that they may “waste” the premiums paid upfront if they have not encountered an accident before the policy expires; thus, they will reduce their accident-prevention efforts, although the premiums are sunk costs and cannot be reversed.

中文翻译：

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上个月要小心：汽车保险保单持有人持有的沉没成本谬论

调查一个独特的大数据集，我们发现汽车保险保单持有人在保险期限的最后一个月比任何其他月份更有可能遇到事故。我们的解释是，这种影响是由保单持有人持有的沉没成本谬论驱动的，这加剧了他们的道德风险。解释是，在最后一个月，保单持有人可能会担心，如果他们在保单到期前没有遇到意外，他们可能会“浪费”预先支付的保费；因此，他们将减少他们的事故预防工作，尽管保费是沉没成本并且无法逆转。