Edinburgh Napier University

  After many years of neglect, freight, freight operations, and commodity flow models are now attracting substantial attention, and there is a wide perception among transportation analysts that they all need a careful overhaul. In this paper the range of applications and issues associated with different forms of freight model are considered. Confusion about what one can do with a given model is often founded on a lack of transparency as to the domain of application for which the model was originally designed and set up. In this paper the authors offer a framework for placing existing freight models in the context of both the temporal targets and the valid domains of application for which they were originally developed. A conclusion of this exercise is that, while existing freight models are simply not up to the task of forecasting future freight activity, there are a number of uses for which these models are well suited. This includes the ability to “predict the present”, an objective and also a technical challenge that has been much under-rated to date. The appropriate action is to assess what the user feels is missing, and to rebalance research efforts to match.