This paper reports on recent experience with the development of Aspace, an Open Source toolkit for the geographic visualization and analysis of activity spaces ? i.e., the set of locations visited by a behavioral agent (e.g., person, household) over time. The paper also briefly examines recent progress with respect to the convergence of Open Source technologies, spatial analysis, and travel behavior research. Aspace has been developed as acollection of functions that, when combined with activity location data, can be used to characterize spatial properties of individual and householdactivity spaces. These properties include, size, orientation, shape, and the geographical dispersion associated with activity locations contained within the activity space. Various planar geometries (e.g., circles, ellipses, irregular polygons) are used to translate measurable spatial properties into intuitive objects for visualizing spatial patterns of activity participation. The toolkit is distributed as a downloadable "package" from theOpen Source R Project for Statistical Computing.
Abstract