Resumen
Increasing sustainability of urban transport systems is a crucial objective of all strategic plans both at national and European level. Different strategies and measures can be adopted to improve the efficiency of transport systems, according to a large set of factors that can affect the results of the implemented actions. A comprehensive study has been carried out in order to define a methodology able to define effective and efficient strategies and measures, allowing to increase the sustainability level of different kinds of cities, from small-medium sized to large metropolitan areas. The methodology has been tested on a group of 50 Italian cities, whose characteristics have been analysed through an initial set of more than 200 indicators. Three main groups of indicators have been taken into account: State indicators, Sustainability indicators, Policy indicators. The main aim has been to identify existing relationships between Sustainability and Policy indicators for cities showing commonalities in terms of State indicators. A correlation analysis allowed to identify 53 relevant indicators from the initial set of 200, while a cluster analysis, based on a hierarchical model, allowed to group the cities into five different groups, according to their population size and density. Correlations between relevant indicators have also been analysed within each group, while linear regression models have allowed to describe some functional relations between Policy and Sustainability indicators. A benchmarking exercise has allowed to identify strategies and measures adopted by the best performers within each group, hence defining possible paths to a better sustainability level for the remaining cities. Finally, recommendations for a correct urban mobility planning procedures have been produced.