Sociological Science 3:39-60. 10.15195/v3.a3.
It is often pointed out that conclusions about intergenerational (parent–child) mobility can differ depending on whether we base them on studies of class or income. We analyze empirically the degree of overlap in income and social mobility; we demonstrate mathematically the nature of their relationship; and we show, using simulations, how intergenerational income correlations relate to relative social mobility rates. Analyzing Swedish longitudinal register data on the incomes and occupations of over 300,000 parent–child pairs, we find that social mobility accounts for up to 49 percent of the observed intergenerational income correlations. This figure is somewhat greater for a fine-graded micro-class classification than a five-class schema and somewhat greater for women than men. There is a positive relationship between intergenerational social fluidity and income correlations, but it is relatively weak. Our empirical results, and our simulations verify that the overlap between income mobility and social mobility leaves ample room for the two indicators to move in different directions over time or show diverse patterns across countries. We explain the circumstances in which income and social mobility will change together or co-vary positively and the circumstances in which they will diverge.