A Research on Mixed Stochastic User Equilibrium Model Based on Generalized Travel Disutility under ATIS

This paper presents a mixed stochastic user equilibrium traffic assignment model in road networks served by advanced traveler information systems (ATIS). All travelers are divided into two groups, equipped and unequipped with ATIS respectively. A concept of generalized travel disutility is introduced based on three criteria, travel time, travel cost and travel time reliability. Generally, travelers equipped with ATIS may not always find the optimal route as a result of imperfect information service, thus, it is assumed that all travelers make their route choices in a logit-based stochastic manner, but with different degree of uncertainty of travel disutility on the road network. The model is formulated as a variational inequality problem and solved by a heuristic solution procedure. A numerical example on a small road network is presented to validate the proposed model and algorithm, at the same time, some important findings are obtained.