Tactical model for the exit choice
Pedestrians exhibit many intelligent behaviors. For instance, experiments show that load balancing occurs over different possible exits, optimising the global leaving time. In the literature, basic tactical models for the exit choice solely depend on the distance to the exits. They do not reproduce load balancing when the pedestrians are initially inhomogeneously distributed. More sophisticated models based on simulation prediction of the travel time over the possible exits allow describing the balancing. Yet, they are numerically very costly.
The travel time is related to the speed of the pedestrian. Yet the pedestrian speed is relatively well described by the pedestrian fundamental diagram, a phenomenological relation linking the speed (or the flow) to the density. In the distance- and density-based tactical model, the choice of the exit is determined by a linear combination of the distance to the exit and the density in front of the exit. A linear discriminant analysis allows to calibrate the coefficients. Simulation results show that the minimal model is able to reproduce the load balancing without requiring complex calculations for the travel time.