What do surveys on marital preferences reveal about inequality trends, and how can they guide method selection?
Abstract
By analysing the joint educational distribution of couples in multiple generations, we can infer both changes in educational homophily and trends in inequality between groups with differing income-generating abilities. These data are available for far more countries and decades than individual or household level income data. Thereby, they allow us to document inequality trends in societies and periods that have not previously been analysed with microdata. To study inequality dynamics using couples’ data, however, one needs to apply methods that control for changes across generations in the structural availability of potential partners with various traits. It is well documented that empirical findings on homophily trends in general – and particularly for the United States in recent decades – are highly sensitive to the choice of method applied. Method selection must therefore be undertaken with particular care. In this study, we draw on Pew Research Center’s surveys conducted in 2010 and 2017, which capture Americans’ self-declared preferences regarding the educational attainment of spouses and partners. Compared to analyses based on a single survey wave, our approach has the advantage of disentangling generational and age effects, allowing us to measure the generation-specific preferences at the core of our research independently of life-course changes in respondents’ preferences. Our analysis confirms the conclusion of an earlier study based on data from a single survey year: namely, that the generation-specific preferences of Americans born after World War II exhibit a U-shaped pattern. The robustness of this pattern to controlling for the age-effects provides an even stronger basis for challenging the applicability of a method widely used in the literature – particularly up to the late 2010s – for studying revealed preferences. At the same time, it lends even stronger support to a recently proposed alternative method.
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