UC Irvine Institute of Transportation Studies

The objective of this research is to establish causality in the interrelationships among household travel time expenditures by mode and car ownership, conditional upon exogenous changes in factors such as income, the numbers of household workers and drivers, and stage in the family life cycle. Panel data with extended travel diary periods (of, say, a week's duration) provide a unique opportunity to understand how households balance their levels of time expenditures and car ownership, and how they adjust these levels in response to exogenous changes. Such an opportunity is provided by the Dutch National Mobility Panel (1984-1988), and in the Netherlands an appropriate breakdown of travel modes is: car (driver and passenger), public transport (including bus, tram, subway, and train), and nonmotorized modes (including bicycle and walking).