Mode choice of complex tours

The modeling of choice can be taken at different levels. In the long run there is a question as to which mode the travelers pre-commit themselves through the purchase of cars, motorcycles or public transit tickets. In the short run one can look at the level of the trip or the level of the tour, i.e., a sequence of trips starting and ending at the same place. The sequence of tours between the first departure and the last return to the home forms the daily activity chain. Traditionally the focus of analysis has been the individual trip, i.e., the movement between two meaningful and substantial activities. In this type of analysis each trip was seen as an independent event, for which the traveler made a new and separate decision with regard to mode, destination, timing, company etc. As long as symmetrical work tours (home-work-home) were the vast majority of morning travel and as long as they were the main concern of transport planning, this assumption was defensible. This is not the case anymore: the pattern of trip making and therefore the tours have become more complex; the long afternoon peak with its mixture of work shopping and leisure travel is now the main concern and the time of maximum demand. This paper addresses these issues by providing a descriptive analysis of these changed patterns and by analyzing mode choice at the tour level. The tour level is relevant because it has long been known that travelers maintain their mode during a tour, especially if they use an individual vehicle. The most variability is observed for tours involving public transport, as the travelers can easily include walking or taxi trips because they do not have to return to their parked vehicles.