Figure 3.

Route choice algorithm for individual pedestrians. (a) Outline of the route choice algorithm. An initial decision on a route can be revised later if individuals are in a queue or reach an intermediate target. Individuals assess their relative preference for different routes using a gain function (see equation (3.1)), which is zero for similar routes and tends to −1 or 1 when the difference between routes is large. Panel (b) shows this gain function plotted against estimated times to complete a reference and an alternative route (see text and equation (3.1) for details). (c) Example to illustrate travel time estimation of individuals. A pedestrian (shown as a dashed red oval at the bottom of the panel) has to choose between two routes. One exit is clear (dashed green lines) and the other is blocked by a short queue (solid blue lines). The estimated travel time is the sum of the time needed to reach a queue or exit location (t_actual), the expected time of waiting in a queue (t_jam) and the time needed to reach the final target after passing through an exit (t_after). Simulated pedestrians compare the relative merit of the alternative routes using the gain function shown in equation (3.1). (Online version in colour.)