Family matters: Development of new family interrelationship variables for US IPUMS data projects

In demographic datasets, researchers frequently want to identify how members of a household are related. In this paper, we develop a new method of estimating parental and spousal relationships using data on fertility patterns and family interrelationships. The improved method includes cohabiting and same-sex couples and is comparable across all modern US IPUMS data projects. A detailed variable indicates how the relationship was inferred and the level of ambiguity around that inference. The new IPUMS family interrelationship variables are very accurate, matching self-reported spouse/partner for 99.99% and parent for over 99.00% of respondents. Among those identified as same-sex couples, we match self-reported spouse/partner for 100% of respondents, 87.57% of whom self-identify as lesbian, gay, or bisexual. We further demonstrate that the new family interrelationship variables closely track temporal variation in teenage fertility.