标题： 教育同质性的历史趋势是U型的还是非U型的？ 或者，如何设定一个标准来选择标准？ 显示英文标题

标题： Historical trend in educational homophily: U-shaped or not U-shaped? Or, how to set a criterion to choose a criterion?

摘要： 测量不同教育群体之间总体不平等的变化通常通过量化教育婚姻同质性在连续世代之间的变化来实现。 然而，当适婚个体的教育水平具有世代特定性时，这项任务变得具有挑战性。 为了解决这一挑战，分类婚姻文献中提出了各种指标。 在本文中，我们回顾了一组指标必须满足的标准，以被视为同质性与不平等的合适度量。 我们的分析标准包括对所区分的教育类别数量的稳健性以及代际流动性和同质性之间的负相关关系。 此外，我们还在美国全国及次国家级别1960年至2010年间同质性的已识别定性历史趋势上施加了一个实证标准。 我们的分析表明，虽然一个特定的基数指标满足所有三个标准，但许多常用的指数并不满足。 我们建议将这个表现良好的指标应用于量化任何国家（包括欧洲国家）的总体不平等趋势，前提是这些国家有夫妻教育水平的人口数据。 显示英文摘要

摘要： Measuring changes in overall inequality between different educational groups is often performed by quantifying variations in educational marital homophily across consecutive generations. However, this task becomes challenging when the education level of marriageable individuals is generation-specific. To address this challenge, various indicators have been proposed in the assortative mating literature. In this paper, we review a set of criteria that indicators must satisfy to be considered as suitable measures of homophily and inequality. Our analytical criteria include robustness to the number of educational categories distinguished and the negative association between intergenerational mobility and homophily. Additionally, we also impose an empirical criterion on the identified qualitative historical trend in homophily between 1960 and 2010 in the US at the national and sub-national levels. Our analysis reveals that while a specific cardinal indicator meets all three criteria, many commonly applied indices do not. We propose the application of this well-performing indicator to quantify the trend in overall inequality in any country, including European countries, with available population data on couples' education level.