Defining and measuring the spatial dimension of accessibility.

This study combines a literature search and review with a real-world survey to identify, compare, and contrast techniques of measuring accessibility in conceptual and operational terms. An hypothesis-based approach is employed to ascertain how these techniques are used in the public and private sectors. With emphasis on the spatial dimension of accessibility, the thesis examines the definition of accessibility, the relative use of different accessibility measurement techniques, and the units used to measure spatial separation. The thesis also explores barriers to accessibility, the criteria and relative importance of spatial and aspatial factors in making location, network and routing decisions, and the use of GIS to implement accessibility measurement techniques. Results suggest that, despite differences in goals and/or objectives, there are similarities between the public and private sectors in both the conceptual and operational aspects of accessibility measurement, the criteria used to make location and transportation network decisions, and the limited use of Geographic Information Systems (GIS) to implement accessibility measurement techniques