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 wit h existing conventional rail (CR) lines, since these corridors typical ly have large markets concentrated around major cities. This paper for mulates a new analytical model to estimate market shares of HSP, and C R 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 choi ces are assumed by minimizing the ''generalized total travel time''. T he relationship among demand-supply attributes such as value of time, train departure time, speed, trip length and fares is explored to iden tify market boundaries by comparing different routing strategies for e ach type of passenger. Individual route choices are aggregated by accu mulating a transformation probability density function of value of tim e to estimate the spatial distribution of markets for two types of rai l lines. The result estimates detail market distributions for passenge rs alighting at stations along the corridor. HSRs are shown to best se rve medium- to long-trip markets, while CRs are shown to serve best fo r commuter travel and as feeders for the HSRs.