New Generation of Dutch National and Regional Models - an Overview of Theory and Practice
D Joksimovic, Ministry of Infrastructure and the Environment; R van Grol, Significance, NL
This paper deals with the new generation of Dutch national en regional models that are used to make forecasts of mobility in general and the traffic and transport conditions in particular for the long-term future.
This paper deals with the new generation of Dutch national en regional models that are used to make forecasts of mobility in general and the traffic and transport conditions in particular for the long-term future. The models are used for two main purposes: a) answering policy questions regarding to e.g. major infrastructure investments en b) to forecast the effect of regional infrastructure projects in the exploration and planning phase.
The overall focus of the new generation of models was to realize maximum consistency. In the old situation the techniques of the models were in principle the same, but in practice many small differences and deviations resulted in different outcomes that were hard to explain. Different implementations of the same models were used as well as different versions of the same software causing differences in input, differences in assumptions, etc.
The new suite of models (one national en four regional models that together cover the whole of the country) is build to ensure maximum consistency. This is realized by using the exact same (version of the) software, by deriving the model inputs from the same sources (corrections are made in the source rather than in the derivatives), by making the exact same assumptions, etc.
In the paper the main reasons for building a consistent system of models for the national and regional level are further explained. The structure of the model as well as the input and output of the model is described in more detail. The most important innovations and major improvements regarding to the previous version of the models are described. The lessons learned regarding to the project organization of the project are discussed. Finally, the results of case studies will be used to illustrating the improvements of the developed model.
Association for European Transport