Properties of boundedly rational user equilibrium under satisficing rule in traffic assignment problem

Based on the framework of Simon's bounded rationality and satisficing rule, this paper investigates the traffic assignment problem in parallel network under boundedly rational user equilibrium (BRUE) condition. By introducing the concept of aspiration level, we first develop a novel model for the problem. The user heterogeneity is then considered according to aspiration level and preference to different routes. Properties and conditions required for the existence of BRUE are derived. The analytical results show that the user aspiration levels on the preferred route are no lower than that on the sub-preferred route. We also find that the BRUE condition can be reduced to the UE condition under certain conditions. Furthermore, the numerical result shows that the total travel times by various BRUE flow patterns are always no lower than that by UE flow pattern.