Models for Pedestrian Behavior
  The behavior of pedestrians shows certain regularities, which can be described by quantitative (partly stochastic) models. The models are based on the behavior of individual pedestrians, which depends on the pedestrian intentions and on the aspects of movement. The pedestrian intentions concerning a sequence of destinations are influenced by the demand for certain kinds of commodities, by the location of stores selling these, and by the expenditures to get the required commodities. The actual pedestrian movement starts and ends at special city entry points like parking lots. It is guided by the pedestrian intentions, but is subject to deceleration processes and avoidance maneuvers due to obstacles. As a consequence, the pedestrians have to speed up to reach the next destination well-timed. In addition, the pedestrian behavior is influenced by unexpected attractions (e.g. street artists). The model for the behavior of individual pedestrians is an ideal starting point for computer simulations of pedestrian crowds. Such simulations take into account the limited capacity of pedestrian ways and places, and allow to determine an optimal design of pedestrian areas and an optimal arrangement of store locations. Therefore, they can be applied for town- and traffic-planning. The model for the behavior of individual pedestrians also allows the derivation of mathematical equations for pedestrian crowds and for pedestrian groups. Pedestrian crowds can be described by a stochastic formulation, by a gaskinetic formulation or by a fluiddynamic formulation. The gaskinetic formulation (mezoscopic level) can be derived from the stochastic formulation (microscopic level), and the fluiddynamic formulation (macroscopic level) from the gaskinetic formulation. 
Dirk Helbing