Comment – Income segregation in cities: A reflection on the gap between concept and measurement

[eng] In his study of twelve French metropolises, Jean-Michel Floch argues that the level of segregation, defined as the spatial separation of groups with different living standards within cities, is higher, in the city‑centres as well as the suburbs than in the outer-suburbs. It is also more marked in the higher living standards. This commentary argues that income segregation in French cities is low for international standards. Based on issues around the measurement . and comparability of income segregation indices, it elaborates on three issues. The first is that, contrary to popular belief, the segregation of poverty contributes little to overall city segregation, while the segregation of affluence as a large contributor remains under-debated. The second is that an empirical or normative benchmark for segregation is needed to frame the discussion around “ too much” segregation. The third is that the actual degree of physical disconnection between income groups, and between income groups and city amenities and services, is not truly measured by current income segregation measures, limiting the usefulness of such measures for policy designs.