A model for market share distribution between high-speed and conventional rail services in a transportation corridor

High-speed rail (HSR) lines are usually planned to serve corridors with existing conventional rail (CR) lines, since these corridors typically have large markets concentrated around major cities. This paper formulates a new analytical model to estimate market shares of HSP, and CR in a fundamental way, and from an individual behavior point of view. Passengers are divided into those who can take an HSR train directly to their destination stations and those who cannot. Optimal route choices are assumed by minimizing the ''generalized total travel time''. The relationship among demand-supply attributes such as value of time, train departure time, speed, trip length and fares is explored to identify market boundaries by comparing different routing strategies for each type of passenger. Individual route choices are aggregated by accumulating a transformation probability density function of value of time to estimate the spatial distribution of markets for two types of rail lines. The result estimates detail market distributions for passengers alighting at stations along the corridor. HSRs are shown to best serve medium- to long-trip markets, while CRs are shown to serve best for commuter travel and as feeders for the HSRs.