Analysis of Travel Time in Multiple-Purpose Trips

This paper investigates the travel time attributed to each activity in a trip chain by developing a travel-time price for multiple-purpose trips. Travel-time price is a ratio of the associated travel time of an activity to the activity duration. The travel-time price developed here has three characteristics. First, it accounts for the influence of sociodemographics and urban form characteristics on travel time. Second, it represents the intra-activity trade-off of travel time between activity duration and its associated travel time for different activity types. Third, it represents the interactivity trade-off of travel time between different types of activities. By using the data from the AMADEUS activity-travel diary collected in the Netherlands in 2000, a regression analysis was carried out for multiple-purpose trips stemming from one base, and the results were compared with those of an analysis of single-purpose trips from one base. The focus was on weekday, nonwork, out-of-home activities performed by heads of households. This daily activity behavior is interpreted as an outcome of the long-term decisions made about work and housing locations. The results indicated that, although multiple-purpose trips are not as common, they are more efficient than single-purpose trips. Sociodemographics and spatial characteristics were not statistically significant for the travel-time price of maintenance activities but were mostly significant for discretionary activities. In addition, nonwork out-of-home travel time is largely influenced by the duration of discretionary, activities, gender, working hours, and the spatial setting.