报告时间：2017年8月28日下午4:00
报告地点：科技大厦11层交通系统科学与工程研究院大会议室
报告人：杨海教授

1、Public transit service frequency and fares with heterogeneous users under monopoly and alternative regulatory policies

Abstract: The conflicting arguments on the issue of frequency undersupply or oversupply imply an inadequate understanding in the connection between the transit market and the commodity market shown in Spence (1975). To resolve the frequency supply issue and elucidate the correspondences between the two markets, we present a model on public transit service frequency and fares with heterogeneous users under monopoly. In a monopoly transit market, there exists an interplay among passengers, the transit operator and the regulator. Passengers are heterogeneous in both willingness to pay (WTP) and value of time (VOT). Transit operator’s objective is considered to be a weighted combination of profit and consumers’ surplus. Propositions of marginal cost pricing, free public transport and price elasticity at the optimum are revealed with generally heterogeneous users. The optimal frequency rule of square root formula is provided. Alternative regulatory policies and influences are analyzed. The equivalent influences of fiscal regulation and goal regulation are proved. The need or justification for transit subsidization is investigated. The issue of frequency undersupply or oversupply is fully resolved. A decision tree is generated and the cases considered in previous studies correspond to only specific branches in our decision tree respectively.

2、Itinerary Choice and Ticket Pre-booking for a Schedule-based High-Speed Rail (HSR) System

Abstract: This paper formulates and examines the passenger flow assignment problem in high-speed railway (HSR) systems with multiple-class users and seats, given the train schedules and time-varying demand. Particularly, we take into account advance booking cost of travelers in the assignment model. Rather than a direct approach to model advance booking cost with an explicit cost function, we consider advance booking cost endogenously, which is determined as a part of the passenger choice equilibrium. We show that this equilibrium problem can be formulated as a linear programming (LP) model based on a three-dimensional network representation of time, space, and seat class. At the equilibrium solution, a set of Lagrange multipliers of the LP model are obtained, which are associated with the rigid in-train passenger capacity constraints imposed by seats. We found that the sum of the Lagrange multipliers along a path in the three-dimensional network reflects the advance booking cost of tickets (to guarantee availability) perceived by the passengers. Numerical examples are presented to demonstrate and illustrate the proposed model for the schedule-based HSR passenger assignment problem.