The GCOST~TM model for demand estimation

摘要

The privatised railway in Britain has brought increased funds for investment, but less time for implementation. This brings the problem of how accurate demand forecasting can occur in the limited time available. The GCOST~TM TM model is a recently-developed spreadsheet-based application which is both behaviourall-sound and and reasonably accurate. It is based on conventional generalised cost (gc) theory, with the elements of gc being entered for a relatively limited number of traffic zones. Total traffic levels can be estimated from a gravity-based formulation if Census-type statistics (e.g. on population, and trip distribution by all modes) are not available. A logit statistical function is applied to the total gc of each mode of transport for each Origin:Destination pair to allocate traffic between the modes. A pair of models has even been used in a hierarchic application of logit modelling.