Though the shortcomings of the four-step modelling process in transportation planning are obvious, most transportation planning systems in practical use are based on it. However, advanced disaggregate models are known to estimate and forecast trip-tables. VISEM, a planning system used in various cities throughout Europe and Asia, applies these sophisticated models. Comments on the methods and the data modelling reflecting the planning objective and the available data are made. The experience gained in a variety of land-use studies is presented to demonstrate the range of applications already carried out. VISEM simulates activities, trip chains are computed as a result. Although important dependencies within the trip-chains important dependencies within the trip-chains are covered, the system does not require extensive computing power due to aggregation of individuals to behavioural homogeneous groups. The models are calibrated and validated with the help of disaggregated survey data as well as aggregated census data. Revealed and stated preferences can be adopted within the models. The models are strongly tied to an urban and regional transportation planning system with the final objective to estimate mode specific traffic volumes in a more realistic manner than it is presently done using conventional four steps. (A)
Abstract