Effects of timetable related service quality on rail demand

This paper is concerned with the suitability of and component weightings within the composite index Generalised Journey Time (GJT). GJT is used to model rail demand in Britain and is composed of station-to-station journey time, service headway and a penalty for the need to change trains. We analyse a large data set of rail ticket sales data to explore three features of GJT. The first is to determine how GJT impacts on rail demand, including interactions with distance and value for money and exploring the effects of the size and sign of the change in GJT, distinguishing between short run and long run effects. The new evidence obtained was important given concerns over the elasticities previously recommended for use in the rail industry in Britain. Secondly, we provide evidence as to whether the weights associated with headway and interchange in GJT are appropriate. Our analysis indicates that more influence should be attached to interchange. Finally, the rail industry in Britain's approach of using GJT and fare is quite unique. We have tested how it compares with the more traditional approach of generalised cost and with the specification of separate elasticities to the component parts of GJT. This indicates that the GJT approach is preferable to the more conventional approach although there would seem to be value in further pursuing separate elasticities to the components of GJT.