Impact of ancestry categorisations on residential segregation measures using Swedish register data.

ABSTRACT

AIM: Country-of-birth data contained in registers are often aggregated to create broad ancestry group categories. We examine how measures of residential segregation vary according to levels of aggregation. METHOD: We use Swedish register data to calculate pairwise dissimilarity indices from 1990 to 2012 for ancestry groups defined at four nested levels of aggregation (1) micro-groups containing 50 categories, (2) meso-groups containing 16 categories, (3) macro-groups containing six categories and (4) a broad Western/non-Western binary. RESULTS: We find variation in segregation levels between ancestry groups that is obscured by data aggregation. CONCLUSIONS: This study demonstrates that the practice of aggregating country-of-birth statistics in register data can hinder the ability to identify highly segregated groups and therefore design effective policy to remedy both intergroup and intergenerational inequalities.