Primal Method for Determining the Most Likely Route Flows in Large Road Networks

This paper presents a method to identify the set of routes and their flows in a user-equilibrium traffic assignment solution. We present a general consistency condition that is satisfied by any set of minimum-cost routes, and show how it can be used in choosing a set of routes that is likely to be similar to the set of user-equilibrium routes. The proposed consistency condition is also essential for finding the entropy-maximizing route flows solution, which may be regarded as the most likely one. An efficient method for finding the entropy-maximizing solution is presented. Numerical results on several networks, including one of large scale, demonstrate the effectiveness of the proposed method. In most cases the method achieves a duality gap of practically zero in a short computation time.