Capacity-constrained mean-excess equilibrium assignment method for railway networks

The reliability and unreliability of travel time variability caused by stochastic train delays considerably influence passengers’ travel path choices. This paper proposes an equilibrium assignment method that can capture the passengers’ path choice behaviors considering both the reliability and unreliability of travel time variability in the railway network. The passengers’ travel path choices are modeled using the mean-excess travel cost (METC), which is the combination of the conditional expectation of travel cost exceeding the effective travel cost, and the endogenous advanced ticket booking cost associated with the rigid train capacity. In general, heterogeneous passengers with different risk-aversion attitudes toward stochastic train delays evaluate their travel options differently and have different requirements for successful transfer. Therefore, first, the passengers’ transfer options are modeled with the concept of METC based on the delay distribution of the two connecting trains. Subsequently, the METC of the passenger trips is calculated. A mean-excess passenger flow assignment model is formulated based on the user equilibrium condition. A path-based capacity-constrained passenger assignment algorithm is designed to solve the model. Moreover, three illustrative examples are presented to demonstrate the effectiveness of the model and solution algorithm.