Human mobility patterns at the smallest scales

TL;DR

This study investigates human mobility at small scales within a university, revealing Brownian motion characteristics with a scaling exponent near 0.5, and discusses how mobility patterns transition at larger scales.

Contribution

The paper introduces a novel methodology for analyzing small-scale human mobility using Wi-Fi access point data and explores the transition from Brownian to non-Brownian motion across scales.

Findings

Mobility at small scales exhibits Brownian features with an exponent close to 0.5.

A new measure of flux is proposed to estimate non-Euclidean distances between access points.

The transition scale from Brownian to non-Brownian motion is identified and discussed.

Abstract

We present a study on human mobility at small spatial scales. Differently from large scale mobility, recently studied through dollar-bill tracking and mobile phone data sets within one big country or continent, we report Brownian features of human mobility at smaller scales. In particular, the scaling exponents found at the smallest scales is typically close to one-half, differently from the larger values for the exponent characterizing mobility at larger scales. We carefully analyze $12$-month data of the Eduroam database within the Portuguese university of Minho. A full procedure is introduced with the aim of properly characterizing the human mobility within the network of access points composing the wireless system of the university. In particular, measures of flux are introduced for estimating a distance between access points. This distance is typically non-euclidean, since the spatial constraints at such small scales distort the continuum space on which human mobility occurs. Since two different exponents are found depending on the scale human motion takes place, we raise the question at which scale the transition from Brownian to non-Brownian motion takes place. In this context, we discuss how the numerical approach can be extended to larger scales, using the full Eduroam in Europe and in Asia, for uncovering the transition between both dynamical regimes.