PERFORMANCE MODELS OF FLEXIBLY ROUTED TRANSPORTATION SERVICES

This paper critically reviews models to predict the performance of flexibly routed transfortation services such as taxi and dial-a-ride. Models of these services have been developed to assist in system design, in evaluation of alternatives, and in regulation. The approaches to modelling such services have been simulation, empirical, deterministic queuing and stochastic processes. Application of several models is illustrated by forecasting the level-of-service on six existing systems. While a good deal of effort has gone into model development and while some of the models appear to be quite accurate, an open question remains as to the acceptance and use of these models by planning and operating agencies.