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

Abstract

The application of Statistical Physics to social systems is mainly related to the search for macroscopic laws, that can be derived from experimental data averaged in time or space,assuming the system in a steady state. One of the major goals would be to find a connection between the statistical laws to the microscopic properties: for example to understand the nature of the microscopic interactions or to point out the existence of interaction networks. The probability theory suggests the existence of few classes of stationary distributions in the thermodynamics limit, so that the question is if a statistical physics approach could be able to enroll the complex nature of the social systems. We have analyzed a large GPS data base for single vehicle mobility in the 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 an universal function describing the distribution. Our conclusion is that understanding the system complexity requires dynamical data-base for the microscopic evolution, that allow to solve both small space and time scales in order to study the transients.

The scaling of human mobility by taxis is exponential

“…They also identify vehicle stop positions and discover single trip length distribution deviates from an exponential and favors a power law gradually when trip length becomes longer. In summary, the results of urban mobility in [13] and [11] are consistent with ours. Thus, it can be conjectured that the phenomenon may not happen accidentally and exist in urban areas of cities widely.…”

“…Similar results are also discovered from GPS trackings [9,2,10,11,12,13], wireless network traces [14], check-ins from locationbased services [15,16] and even movements of banking notes [17].…”

Smart cities of the future

“…9(b) we show the spatial distribution of the daily individual mobility derived from GPS private car data: the straight line in a logarithmic scale implies an exponential decay with the length that reminds us of the statistical Boltzmanns distribution. The results shed lights on the average traffic properties in a city, but future microscopic data will allow us to study the evolution of transient states from a microscopic (individual) point of view [10]. This also opens new research opportunities that use microscopic mobility data as a paradigm to study the human decision mechanisms and the information based interactions.…”

Spatial networks

“…Recent studies [46,262] used GPS data of private vehicles for the city of Florence (Italy). and have shown that the total daily length trip is exponentially distributed (see Fig.…”