Study of human mobility patterns through the use of mobile phone communication
.
Abstract Book of the XXIII IUPAP International Conference on Statistical Physics, Genova, Italy, (9-13 July 2007)Abstract
If you have a cell phone, your carrier knows always your whereabouts. In
industrial countries with almost 100% mobile penetration, these records
represent a huge
opportunity to science, offering access to patterns of human mobility at a level
and detail unimaginable before. Each cell phone communicates with the closest
towers, which naturally partition a country into distinct geographic cells.
Given that
calls are recorded for billing purposes, one can reconstruct the movement of
each mobile
phone user. Using a data set over a million of individual displacements, we
quantify the main features of human daily travels witihin a country. First, the
distribution of traveling distance decays as a power law. Second, individuals
move
in confined areas with a characteristic length or radius of gyration, with the
distribution of this radius being heavy tailed. We show that human traveling
behavior can be
described mathematically on many spatiotemporal scales to a surprising accuracy
by a sort of centrally biased random walk.