The dynamic of residential segregation in Italian metropolises: Milan, Rome and Naples, 1991-2011

We investigate how socio-residential segregation has changed between 1991 and 2011 within the three biggest Italian metropolitan areas: Milan, Rome and Naples, using the OECD methodology to define the perimeters of the latter. We data of the three last waves of the Italian population census (1991-2001-2011) at the finest scale (census sections).To build a reliable (and internationally comparable) socio-professional typology, we have worked directly on the census microdata at the individual level to create a new variable of socio-professional positions. This variable has been created on the basis of individual answers to three questions, one related to the ISCO, one related to the type of job contract, and one related to the sector of activity. The combination of the three produces a more informative socio-professional scale, well adapted to compare the social segregation dynamics of Italian metropolises with those of other European metropolises (particularly London and Paris). To analyze residential segregation, we then build a typology of spaces based on the weight of the various socio-professional categories within the active resident population of each space. This is done following the methodology created by Préteceille to study residential segregation in France and Brazil, and further developed by Cousin&Préteceille to compare Milan and Paris at the beginning of 90s. This method of neighborhoods classification is based on a combination of ascending hierarchical classification techniques and correspondence factor analysis. The paper presents data, methodology, and a description of the main dynamics of urban change in the three metropolises between 1991 and 2011. It asks one main research question related to the residential behavior of middle classes, and then tests and nuances two hypothesis related to: (1) the reduction of social mix in the core neighborhoods of each metropolitan area, and to (2) upper-middle classes secession.