This paper illuminates how three distinct but complementary concepts can be used to explain the prevalence of inbreeding in some contexts and the absence or limited frequency of inbreeding in others. The concepts of internal and external labour markets can be useful in understanding the academic labour market conditions that may support or discourage inbreeding. The concepts of vertical fragmentation of the academic labour within universities and the vertical stratification of institutions within systems can be helpful in understanding why inbreeding may be more prevalent for some categories of academic labour, located within specific institutional contexts, than others. Finally, the concepts of social and cultural capital can be useful in understanding inbreeding in terms of academic hiring decision processes.

中文翻译：

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重新定义近亲繁殖现象：劳动力市场、分层和资本

本文阐明了如何使用三个不同但互补的概念来解释在某些情况下近亲繁殖的普遍性以及在其他情况下近亲繁殖的缺失或频率有限。内部和外部劳动力市场的概念有助于理解可能支持或阻碍近亲繁殖的学术劳动力市场状况。大学内学术劳动力的纵向分散和系统内机构的纵向分层的概念有助于理解为什么在特定机构环境中的某些学术劳动力类别中近亲繁殖可能比其他类别更普遍。最后，社会和文化资本的概念有助于从学术招聘决策过程中理解近亲繁殖。