A REVIEW OF ACTIVITY-BASED TRAVEL BEHAVIOR RESEARCH

The Activity-based travel behavior theories mainly study individual or households' travel behavior laws and decision characters in trip chain. An abundant research harvest has been gained since the systematical studies were carried through in western countries. This paper firstly introduces the origin of activity-based travel behavior research. The activity-based approach to the analysis of travel behavior and travel demand originated in the UK, the US and Germany in 1970's to overcome the limitations of the standard four-stage approaches. The starting point of the approach was the switch of focus from aggregate trip making to individual activity participation and the identification of travel as a derived demand. Then the development and fruits of activity-based travel behavior research in western countries are systematically illustrated, including the fundamental theories, study methods, and the activity-based travel demand model systems. The activity-based travel theory can be summarized in two basic ideas: first, the demand for travel is derived from the demand for activities. Secondly, humans face temporal-spatial constraints. A substantial amount of analysis has been done to refine the theory, test specific behavioral hypotheses, and exploratory methods of modeling important aspects of activity-based travel behavior. Both theoretical developments are seen as two threads originating from a common behavioral assumption, namely that trip chaining is based on an r-sequential decision making process. The study method of activity-based travel behavior is mainly on three aspects: interspace-based interaction approach, utility-based approach and heuristic approach. These approaches overcome the area division limitations of the four-stage approaches and present day-to-day travel behavior of individuals and households as basic study unit. Activity-based demand forecasting model includes two aspects: econometric model and mix simulation model. These model systems gain development in three successive phases: MTC(Metropolitan Transportation commission)system, Netherlands' tour-based model and day-to-day travel behavior choice model. Finally the status quo and characteristics of travel behavior research in China are analyzed. The results indicate that travel demand deriving from activity demand, people facing the constraint of the time and space, the life style influencing people's decisions, and the travel decisions influencing each other dynamically and mutually under variable conditions. The research is just underway and China should develop the activity-based travel behavior research based on analyzing Chinese travel behavior deeply in order to support traffic planning and decision-making of transport management policy.