Statistical fluctuations in pedestrian evacuation times and the effect of social contagion

ALEXNDRE NICOLAS; SEBASTIÁN BOUZAT; MARCELO KUPERMAN

PHYSICAL REVIEW E - STATISTICAL PHYSICS, PLASMAS, FLUIDS AND RELATED INTERDISCIPLINARY TOPICS

American physical Society

Año: 2016 vol. 94 p. 1 - 12

1063-651X

Mathematical models of pedestrian evacuation and the associated simulation software have become essentialtools for the assessment of the safety of public facilities and buildings. While a variety of models is now available,their calibration and test against empirical data are generally restricted to global averaged quantities; the statisticscompiled from the time series of individual escapes (?microscopic? statistics) measured in recent experiments arethus overlooked. In the same spirit, much research has primarily focused on the average global evacuation time,whereas the whole distribution of evacuation times over some set of realizations should matter. In the presentpaper we propose and discuss the validity of a simple relation between this distribution and the microscopicstatistics, which is theoretically valid in the absence of correlations. To this purpose, we develop a minimalcellular automaton, with features that afford a semiquantitative reproduction of the experimental microscopicstatistics. We then introduce a process of social contagion of impatient behavior in the model and show that thesimple relation under test may dramatically fail at high contagion strengths, the latter being responsible for theemergence of strong correlations in the system. We conclude with comments on the potential practical relevancefor safety science of calculations based on microscopic statistics.