The Identification of Sub-centres in Two Italian Metropolitan Areas: a Functional Approach

This work introduces a method aimed at the identification of metropolitan sub-centres. Instead of using traditional and static methodologies based on morphological approaches (e.g. employment density), interaction measures have been employed, based on the Central Place theoretical tradition. In particular, tools of social network analysis and a measure of productive completeness have been utilised, so as to take into account the capacity of sub-centres to organise their surrounding territory. The degree of node-centrality has been calculated using data about commuting for working reasons and the methodology has been applied to the metropolitan areas of Rome and Milan. Results have been compared with those obtained from the application of Giuliano and Small?s (1991) thresholds in jobs density and absolute employment and confirm the soundness of the proposed approach for Italian metropolitan areas.