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In this paper, we extend some ideas of statistical physics to describe the properties of human mobility. From a physical point of view, we consider the statistical empirical laws of private cars mobility, taking advantage of a GPS database which contains a sampling of the individual trajectories of 2% of the whole vehicle population in an Italian region. Our aim is to discover possible "universal laws" that can be related to the dynamical cognitive features of individuals. Analyzing the empirical trip length distribution we study if the travel time can be used as universal cost function in a mesoscopic model of mobility. We discuss the implications of the elapsed times distribution between successive trips that shows an underlying Benford's law, and we study the rank distribution of the average visitation frequency to understand how people organize their daily agenda. We also propose simple stochastic models to suggest possible explanations of the empirical observations and we compare our results with analogous results on statistical properties of human mobility presented in the literature.

si discute un approccio complesso alla mobilita' urbana basato sulla studio di dati GPS da singolo veicolo

In this paper we present evidence of the existenmce of empirical statistical laws for private car mobility in italina urban systems.

Applicazioni dell Fisica al problema della mabilita' urbanas: dal Carnevale di Venezia ai problemi del traffico

Nel contributo del Laboratorio di Fisica della Citta' (B. Giorgini et al. ) si sono illustrati alcuni modelli per una mobiita' fluida comoda e bella anche durante i periodi di piu' intenso afflusso turistica, non solo per la zona di Senigallia ma per l'intera fascia costiera adriatica

L'antico proverbio sembra suggerire che nulla è più grande della paura. Ma, se riusciamo a sapere perchè, quando e come si manifesta la transizione dinamica che può portare al panico in una situazione di folla, possiamo cercare di disinnescarla o almeno attitirne gli effetti.

The problem of modeling cognitive systems has been recently considered under new point of views. The attention is no more mainly focused on the simulation of rational behaviors, but also on the importance of the individual free-will and of the apparent "irrational decisions". A possible approach for a mathematical modeling is to introduce an internal dynamical structure for the "elementary particles" that allows to define an individual cognitive dynamics at the base of the decision mechanisms. Our assumptions imply the existence of an utility potential which is the result of an evolution process, where some behavioral strategies have been selected to perform efficiently in presence of different environmental conditions. The utility potential defines a cognitive dynamics as a consequence of information based interactions and the choice of a strategy depends on the individual internal cognitive state. This is the definition of an "automata gas model", whose aim is to extend some statistical physics results to cognitive systems. We shall discuss the existence of self-organized dynamical states in an automata gas, that are the result of a cognitive behavior. We show as the introduction of a cognitive internal dynamics allows to simulate the individual rationality and implies the existence of critical conditions at which the system performs macroscopic phase transitions. The application to the pedestrian mobility modeling problem is explicitly considered and we discuss the possibility of a comparison with experimental observations.

Si definisce il campo di ricerca della Fisica della Citta' e si presentano alcuni modelli di mobilita' pedonale e automobilistica, con l'analisi di un ampio insieme di dati sperimentali.

In this new framework, the complex physics, we propose in this paper a modeling of urban mobility based on the physics of the city, essentially in order to understand, describe, explain and, eventually, to predict the origin and the evolution of zigzagging and asystematic mobility, which becomes more and more relevant in the modern and post-modern cities. Moreover implementing the model on a computer, we obtain a virtual urban system, in which we can perform via simulation a large set of experiments, exploring overall the range of the different possible mobility features and criticalities. Finally, we will present a material experiment in order to compare the empirical data with the simulation results, finding a good agreement.

Understanding statistical properties of cognitive systems is one of the main goal of complex systems physics. The automata gas is a statistical system whose particles perform information based interactions and use a decision mechanism. The collective nature of such interactions is at the base of the self-organized dynamical states of the system. In some cases it is possible to study the emergence of these states, by using an adiabatic separation between the single particle time scale and the particle distribution time scale. Then the emergent properties can be related to the solutions of a nonlinear di®usion equation. The considered models have a wide range of application in biology and social sciences to describe the self-organization properties observed in the experiments. Our main interest is to develop a model for the pedestrian dynamics in a urban space. We study the properties of a automata gas in some simple cases and we discuss the comparison with experimental data.

The modern cities have become real laboratories for the scientists interested in complexity and the problem of urban mobility is one of the challenges. The complex natureof city is discussed to stress the role of cognitive dynamics to understand the emergent phenomena that characterize city dynamics. A cognitive behavior model studies the dynamics of living systems able to perform information based interactions with an evolving environment. The application of the mathematical language to define models for cognitive systems has fascinated the scientists from a long time. Nowadays the evolution of statistical systems whose microscopic elements have a cognitive behavior (automatagas) is a research field for complex systems physics. In the second part of the paper, we present a cognitive dynamical model developed to study the problem of individual decisions in microscopic urban mobility.

we study the pedestrian mobility in venezia carnival by using a complex systems approach

We discuss an exponential law for the trajectories distribution in a urban road network, that has been found analyzing a large set of GPS data on private cars dynamics. This law appears to be common for very di®erent cities, from the size of a town to that of a metropolis.We propose to explain this behavior as an effect of the activities sprawling in modern cities, associated with the existence of a cognitive proximity concept that determines the citizens mobility requests We discuss the relevance of these results for a complex systems approach to urban mobility.

Nel presente contributo si traccia un panorama sintetico dei metodi, modelli e risultati in merito alla descrizione, spiegazione e eventuale predizione delle dinamiche di mobilità sul tessuto urbano, ottenuti nell’ambito del Laboratorio di Fisica della Città. La mobilità è un fenomeno assai intricato sia per la moltitudine di decisioni individuali che implica, sia per la molteplicità dei mezzi di trasporto possibili, sia per le implicazioni politico sociali. Per quanto ci riguarda abbiamo lavorato sia alla sperimentazione e acquisizione di dati empirici, sia alla modellazione fisico matematica. Attraverso l’implementazione algoritmica poi abbiamo costruito dei sistemi di simulazione, nel cui ambito è possibile svolgere esperimenti virtuali dedicati a mettere in luce i punti (aree, strade, incroci ecc..) critici, le transizioni di fase (tra ordine e disordine per esempio) e le eventuali soluzioni che si possono prefigurare onde sciogliere la matassa. Sottolineiamo che i componenti elementari dei nostri sistemi sono i singoli individui dotati di libero arbitrio (free will), insomma i cittadini con le loro propensioni di mobilità, e quindi che partiamo dalla microdinamica fisica e decisionale per tentare di arrivare alla dinamica globale. Infine proponiamo uno schema per la costruzione di sistemi per l’e-governance della mobilità, in particolare autoveicolare.

Mobilis e' un modello di mobilita' che descrive una citta' come sistema complesso ed integra la mobilita' pedonale con quella veicolare. Viene proposta una analisi della mobilita' nella fascia costiera del comune di Seniallia, tenendo conto dei principali cronotopi e si effettua un confronto tra la situazione a bassa ed elevata concentrazione turistica.