This article bridges the literature on educational inequality between and within families to test whether high–socioeconomic status (SES) families compensate for low cognitive ability in the transition to secondary education in Germany. The German educational system of early-ability tracking (at age 10) represents a stringent setting for the compensatory hypothesis. Overall, previous literature offers inconclusive findings. Previous research between families suffers from the misspecification of parental SES and ability, while most within-family research did not stratify the analysis by SES or the ability distribution. To address these issues, I draw from the TwinLife study to implement a twin fixed-effects design that minimizes unobserved confounding. I report two main findings. First, highly educated families do not compensate for twins’ differences in cognitive ability at the bottom of the ability distribution. In the German system of early-ability tracking, advantaged families may have more difficulties to compensate than in countries where educational transitions are less dependent on ability. Second, holding parents’ and children’s cognitive ability constant, pupils from highly educated families are 27% more likely to attend the academic track. This result implies wastage of academic potential for disadvantaged families, challenging the role of cognitive ability as the leading criterion of merit for liberal theories of equal opportunity. These findings point to the importance of other factors that vary between families with different resources and explain educational success, such as noncognitive abilities, risk aversion to downward mobility, and teachers’ bias.

中文翻译：

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小康家庭能弥补低认知能力吗？来自双生子研究的早期教育中的社会不平等证据

本文架起了有关家庭之间和家庭内部教育不平等的文献，以测试高社会经济地位（SES）家庭是否可以弥补德国向中等教育过渡过程中认知能力低下的不足。德国的早期能力跟踪教育系统（10岁时）代表了补偿性假说的严格设定。总体而言，以前的文献没有得出结论性的结论。以前家庭之间的研究遭受了父母SES和能力的错误界定，而大多数家庭内部研究并未对SES或能力分布进行分析。为了解决这些问题，我从TwinLife的研究中借鉴了一种实现双固定效应设计的方法，该设计可以最大程度地减少未观察到的混淆。我报告了两个主要发现。第一，受过良好教育的家庭无法补偿双胞胎在能力分布底部的认知能力差异。在德国的早期能力跟踪系统中，与教育过渡对能力的依赖程度较低的国家相比，有优势的家庭可能难以补偿。其次，在保持父母和孩子的认知能力不变的情况下，来自受过高等教育的家庭的学生上学的可能性要高出27％。这一结果意味着对处境不利家庭的学术潜力的浪费，挑战了认知能力作为机会均等自由理论的主要绩效标准的作用。这些发现指出了其他因素的重要性，这些因素因资源不同的家庭而异，并说明了教育成功的原因，例如非认知能力，