How Spatial Segregation Changes over Time: Sorting Out the Sorting Processes

Although there is strong evidence that segregation on socioeconomic lines has risen in many countries over the last few decades, comparatively little is known about the processes by which this happens. While it is often assumed that selective migration is the dominant process, this has rarely been demonstrated. This paper proposes a more comprehensive framework to analyse processes driving changes in segregation—a ‘neighbourhood accounts’ framework. The framework is tested using data from the Scottish Longitudinal Study for 1991–2001, focusing on the working-age population. Contrary to what many have assumed, selective migration is shown to have only a very weak impact on changes in spatial segregation, and is certainly not the dominant factor—at least in this particular context. The effects of ageing or cohort replacement and of uneven rates of status change or social mobility appear much more important. This raises important issues for policies to tackle segregation.