Reliability evaluation of a multistate railway transportation network from the perspective of a travel agent

Travelling by railway trains is usually the preferred option of travelers. Assessing whether a railway company can provide sufficient seats or cabins is meaningful for a travel agent to evaluate how the size of a tour group they can serve. A railway transportation system presents a set of available trains connecting the starting station and the destination station for a tour group according to their itinerary and the train timetable of a railway transportation company. The railway transportation system can be represented as a network with arcs denoting trains and nodes denoting starting, destination, and transfer stations. Because the available seats or cabins (i.e., capacity) in a train may be partially or fully reserved by other agents or groups, the capacity should be stochastic. Accordingly, the system can be modeled as a multistate railway transportation network. System reliability is defined as the probability that a tour group can successfully travel from the starting station to the destination station according to their itinerary, and can be a decision indicator for the travel agent. This study proposes an algorithm based on minimal paths to evaluate the system reliability. A case study of the railway transportation system in Taiwan is analyzed to demonstrate the applicability and computational efficiency of the proposed algorithm.