Statistical laws in urban mobility from microscopic GPS data in the area of Florence

We have analyzed a large GPS data base for single vehicle mobility in Florence urban area, obtaining statistical laws for path lengths, for activity downtimes and for activity degrees. We show also that simple generic assumptions on the microscopic behavior could explain the existence of stationary macroscopic laws, with a universal function describing the distribution. Our conclusion is that understanding the system complexity requires a dynamical data base for the microscopic evolution, which allows us to solve both smal space and time scales in order to study the transients.