Toolkits for Urban Transport Development - UNEP

Annex 5 Four Step Modelling
Model Framework (Four Step Modelling)
The four step model approach for CMP needs to account different social groups and gender (See
Figure 4) and for all modes of transport including NMT, para-transit and public transport and this is
slightly different from conventional four step modelling where there is no differentiation in terms of
socio economic groups and gender and where the focus is mainly on motorised transport. Modeling
softwares like QuantumGIS, ArcGIS, TransCAD, CUBE, VISUM, EMME, OmniTrans, etc can be
used to create the travel demand model of the city. However these softwares are designed primarily
to model motorised modes like cars, two-wheelers and buses. Omnitrans is the only software among
these that has specific modelling capabilities elating to cycle users. Hence adequate care should be
taken in specifying the modelling parameters to suit the softwares for cycles. Various stages of the
modelling procedure have been explained in the following sections.
Figure 2.
Four Step Model Framework
The base year travel demand model is required to replicate the road network and travel patterns of the
city in modelling software and to test for various short term measures that can be taken to improve the
existing transportation systems. The following table gives the input parameters and their data sources
used for developing the base year model.
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