Patterns, entropy, and predictability of human mobility and life

TL;DR

This study analyzes human mobility patterns using smartphone data, revealing heavy-tailed location distributions, regular daily routines, and quantifying the predictability of individual movements based on entropy and transition probabilities.

Contribution

It introduces a method to quantify human mobility regularities and unpredictability using entropy measures and pattern clustering from smartphone data.

Findings

Location patterns follow a power-law distribution with exponent ~-1.7.

Regular daily routines increase mobility predictability.

Predictability extends up to a few hours based on habitual patterns.

Abstract

Cellular phones are now offering an ubiquitous means for scientists to observe life: how people act, move and respond to external influences. They can be utilized as measurement devices of individual persons and for groups of people of the social context and the related interactions. The picture of human life that emerges shows complexity, which is manifested in such data in properties of the spatiotemporal tracks of individuals. We extract from smartphone-based data for a set of persons important locations such as "home", "work" and so forth over fixed length time-slots covering the days in the data-set. This set of typical places is heavy-tailed, a power-law distribution with an exponent close to -1.7. To analyze the regularities and stochastic features present, the days are classified for each person into regular, personal patterns. To this are superimposed fluctuations for each day. This randomness is measured by "life" entropy, computed both before and after finding the clustering so as to subtract the contribution of a number of patterns. The main issue, that we then address, is how predictable individuals are in their mobility. The patterns and entropy are reflected in the predictability of the mobility of the life both individually and on average. We explore the simple approaches to guess the location from the typical behavior, and of exploiting the transition probabilities with time from location or activity A to B. The patterns allow an enhanced predictability, at least up to a few hours into the future from the current location. Such fixed habits are most clearly visible in the working-day length.