• education
• socioprofessional category
• public transport
• accessibility
• sector
• entropy
• gentrification
• Paris
• population

In our work, we estimate the effects of public transport improvements on population structure in the Paris region between 1975 and 2011. This period covers the main stages of the expansion of the regional public transport system, particularly of the Regional Express Rail (RER). We measure the exposure to transport improvements by using an origin-specific, commuting-time based accessibility index, while we measure the spatial distributions of the socio-economic variables (education, sector of activity, profession) by using an entropy index. We find a negative effect of transport improvements on the education, sector and category entropies. Results change when we focus on the municipalities connected by highways or on the municipalities in the inner suburbs: in these cases, the evidence suggests that an increase in accessibility leads to a larger concentration of residents in the higher educational groups.