Institute of Transportation, MOTC

　　This paper proves that there exist some regular characters to the model of the optimal n-step tolls (n = 1, 2, 3, …). According to these regular results, we can then derive the optimal number of pricing steps, which minimizes the total costs for the demand and supply sides, for the step toll scheme implemented at a queuing road bottleneck. These outcomes, which have not been discussed previously, not only improve the theoretical model of the step toll scheme, but also provide the authorities a rule to operate the optimal step toll in practice.