Recent literature has shown that skills are not only essential for the development of successful adults, but also that they are malleable and prone to be affected by many experiences, especially during childhood. This paper examines how bullying depletes skills in school children. I formulate a dynamic model of skill accumulation with endogenous victimization based on the identification of unobserved heterogeneity. I allow victimization to depend on each student’s traits and those of her classmates. Using a unique longitudinal dataset on middle school students, I find that victimization depletes current skill levels by 40% of a standard deviation for the average child. This skill depletion causes the individual to become 25% more likely to experience bullying again. Therefore bullying triggers a self-reinforcing mechanism that opens an ever-growing skill gap. Finally, I find evidence that supports the allocation of students in more skill-homogeneous classrooms as a tool to reduce victimization.

中文翻译：

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受害与技能积累：校园欺凌案例

最近的文献表明，技能不仅对成功成年人的发展至关重要，而且还具有可塑性，并且容易受到许多经历的影响，尤其是在童年时期。本文探讨了欺凌如何消耗学童的技能。基于对未观察到的异质性的识别，我制定了一个内生受害的技能积累动态模型。我允许受害取决于每个学生和她同学的特征。使用一个关于中学生的独特纵向数据集，我发现受害使当前技能水平降低了普通儿童标准差的 40%。这种技能消耗导致个人再次遭受欺凌的可能性增加 25%。因此，欺凌触发了一种自我强化机制，从而打开了不断扩大的技能差距。最后，我发现有证据支持将学生分配到技能更同质的教室中，以此作为减少受害的工具。