Regression-based measure of urban sprawl for Italian municipalities using DMSP-OLS night-time light images and economic data

Night-time light can be used in order to evaluate the degree of urbanization and urban sprawl in a specific territory. In fact, at the local level, the lower the urban density, the higher the per-capita length of collector roads and the area covered by buildings and infrastructures. It follows that the lower the urban density, the higher the municipal luminosity. Urban sprawl is determinant in defining the mobility condition in a specific territory and the service and infrastructure needs. This paper uses regression analyses in order to estimate a 'relative' measure of urban sprawl that takes into account also demographic and economic characteristics. We apply this technique to a panel of Italian municipalities over the period 2004-2012 and compare the resulting measure to the 'absolute' measures provided by the Italian Institute for Environmental Protection and Research in order to evaluate the contribution of our measure to the knowledge of the sprawl phenomenon.