naa a22 4500 528785060 20180924065518.0 cr unu---uuuuu 180924e20100407xx s 000 0 eng 10.3929/ethz-b-000017721 doi 10.1371/journal.pone.0010047 doi (ETHRESEARCH)oai:www.research-collection.ethz.ch:20.500.11850/17721 The Walking Behaviour of Pedestrian Social Groups and Its Impact on Crowd Dynamics [Elektronische Daten] [Simon Garnier, Dirk Helbing, Guy Theraulaz, Mehdi Moussaïd, Niriaska Perozo] PLoS ONE Open access ethresearch Human crowd motion is mainly driven by self-organized processes based on local interactions among pedestrians. While most studies of crowd behaviour consider only interactions among isolated individuals, it turns out that up to 70% of people in a crowd are actually moving in groups, such as friends, couples, or families walking together. These groups constitute medium-scale aggregated structures and their impact on crowd dynamics is still largely unknown. In this work, we analyze the motion of approximately 1500 pedestrian groups under natural condition, and show that social interactions among group members generate typical group walking patterns that influence crowd dynamics. At low density, group members tend to walk side by side, forming a line perpendicular to the walking direction. As the density increases, however, the linear walking formation is bent forward, turning it into a V-like pattern. These spatial patterns can be well described by a model based on social communication between group members. We show that the V-like walking pattern facilitates social interactions within the group, but reduces the flow because of its "non-aerodynamic” shape. Therefore, when crowd density increases, the group organization results from a trade-off between walking faster and facilitating social exchange. These insights demonstrate that crowd dynamics is not only determined by physical constraints induced by other pedestrians and the environment, but also significantly by communicative, social interactions among individuals. Creative Commons Attribution 3.0 Unported http://creativecommons.org/licenses/by/3.0 ethresearch Garnier Simon joint author Helbing Dirk joint author Theraulaz Guy joint author Moussaïd Mehdi joint author Perozo Niriaska joint author PLoS ONE S.l. : Public Library of Science 5 (4), p. e10047 1932-6203 http://hdl.handle.net/20.500.11850/17721 text/html WWW-Backlink auf das Repository (Open access) 1 Journal Article ethresearch ETHRESEARCH 856 40 http://hdl.handle.net/20.500.11850/17721 text/html WWW-Backlink auf das Repository (Open access) ETHRESEARCH 700 1- Garnier Simon joint author ETHRESEARCH 700 1- Helbing Dirk joint author ETHRESEARCH 700 1- Theraulaz Guy joint author ETHRESEARCH 700 1- Moussaïd Mehdi joint author ETHRESEARCH 700 1- Perozo Niriaska joint author ETHRESEARCH 773 0- PLoS ONE S.l. : Public Library of Science 5 (4), p. e10047 1932-6203 BK010053 XK010053 XK010000 ETHRESEARCH ETHRESEARCH ETHRESEARCH Journal Article Open access