Abstract
Individual action space is an important indicator of an individual's ability and flexibility in pursuing daily activities under various constraints. Although a number of studies have explored the size and variability of individual action space, there is a lack of knowledge about how this individual activity space evolves over a long time-span. Using the results of household travel surveys conducted in 1980, 1990, and 2000 in the Osaka metropolitan area of Japan, this paper examines the temporal changes in individuals' action spaces. By composing a system of Tobit models, the stability over time of indices that characterize individuals' action spaces is examined. The results show that the commute distance of workers negatively influences the spread of activity locations, while in the case of nonworkers, activity locations tend to be more dispersed when activities are pursued away from home.
