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When couples were grouped by marriage and cohabitation, age factors were important.
This study examines assortative mating by educational level in cohabitation and marriage in the US.
Data were obtained from the 1960, 1970, 1980, and 1990 US census public use samples, which were large representative samples and included information on both spouses.
Educational homogamy has decreased over time from 1960 to 1990 for younger couples, particularly for those with over and under 12 years of schooling, 13 years over and under, and 16 years over and under.
Increased homogamy has occurred over time for those with over and under 10 years of schooling.
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