Inhomogeneities in dense crowds: a case study on active and passive pedestrians

Abstract

Until now in bottleneck experiments crowds with homogeneous instructions and therewith equal motivation levels were studied. In this article, we use data with four different motivation levels. We consider these crowds homogeneous, as all participants got the same instructions. In one inhomogeneous experiment 20 % of the participants were secretly given the instruction to move extra slow. We investigate how the presence of both active and passive participants influences the dynamics within the crowd and compare the results to those of a homogeneous crowd. Our analysis shows that inhomogeneities can have a significant influence on the results. In density profiles slow participants create distinct regions of lower density and cause a wider spread of waiting times. The flow through the bottleneck in the inhomogeneous run is even lower than for the lowest motivation. Headway analysis highlights how passive participants create free spaces which active participants can use for their advantage.