New instruments for reading urban dynamics in contemporary city. Erlang data as a promising tool for micro scale analysis of urban fabric

This thesis is a contribution to the DAStU research work on the use of cell phone traffic data in the field of urban and territorial studies. It focuses on the potentialities offered by the cell phone data and the application of it as a new tool for reading urban dynamics in a contemporary city. Beginning with the insights of transformations the city is facing nowadays it opens new research tools such as Social Positioning Method (Ahas, 2005) and Mobile Census (Ratti, 2008) that are focused on treating cell phone data able to reflect movements of people and their presence in the space. The objective of this thesis research experiment was to use telephone traffic data provided by Telecom Italia, specifically Erlang data, that can be utilized to describe the intensity of the city use in morning or night hours, during events and holidays. The Erlang data (describes the density of telephone traffic every 15 minutes for areas with a size of 250m x 250m) has been treated in an anonymous and aggregated manner and permitted to construct maps able to visualize the spatial distribution of mobility flows, and was compared with statistical variables derivable from municipal data sources consolidated in order to evaluate possible correlations between the variability in intensity of calls from the cellular network and the variability in urban-settlement conditions. The Erlang trends were transformed into a normalized curves showing average daily calling activity trend in a chosen case study areas. Further study was concentrated on reading population behavior on micro urban scale and describing the time space variations in the use of single urban neighborhood in two different sprawled areas in Milan Urban Region. The analysis carried on mobile phone data showed its potential in accessing information that wasn't available through traditional data surveys and, also the practices of use of cell phone data are proposed as a tool for supporting and increasing the efficiency of urban policies and mobility services.