© Association for European Transport and contributors 2009 1 On Dynamic Traffic Information and Patterns of Cooperative Behaviours: a Probabilistic Model with Economic Analysis

The effects of dynamic traffic information on the network assignment of equipped and uninformed users are modelled analytically to address various patterns of cooperative behaviour among the user classes, including User Equilibrium, System Optimum and Informed Cooperation by minimization of travel cost among the informed users only. A theoretical model is developed for a two link network subject to congestion recurrent and incidental on link travel times, dynamic traffic information, and two classes of users respectively informed and uninformed. Analytical formulae are provided for the main model variables, including average link flow and trip cost by user class, as well as marginal external cost by user class, for each of the two basic patterns of cooperation among the network users: User Equilibrium (UE) and System Optimum (SO). Based on parametric analysis, it is shown that under UE the informed users benefit from dynamic information in a decreasing way with respect to demand volume and equipment rate, wherea