Sibling correlations and SES overlaps in late-career Swedes

To what extent is socioeconomic standing (SES) uni- or multidimensional? SES is typically measured using variables such as education, occupation, income, and, more recently, wealth, but do these variables reflect the same or different hierarchies? This paper uses the methodology of Karlson and Birkelund (2025) to study how sibling correlations, as a measure of the role of family background, overlap across SES dimensions. Four dimensions of SES are considered: education, occupation, income (earnings and disposable income), and wealth. The findings reveal three clusters in the overlap pattern of sibling correlations across these dimensions: (1) education/occupation, (2) income, and (3) wealth. This pattern remains consistent across subsamples defined by sex. The analysis shows that a unidimensional sibling factor, assuming a single latent SES factor, fails to capture the observed sibling correlations adequately. Still, the unidimensional factor accounts for modest to substantial portions of the sibling correlations across outcomes. The evidence for a single latent family factor weakens further when additional outcomes such as crime, cognitive ability, and physical capacity (health) are included in a younger male sample born between 1958 and 1968. A life-course extension shows substantial, though incomplete, stability in the family characteristics shaping income across early-, mid-, and late-career stages. In conclusion, while a unidimensional SES factor exists, it is substantively dominated by multidimensionality in intergenerational transmission.