Summary: | Functionalist static equilibrium models of observed travel behaviour dominate transportation science and planning. Several theoretical and practical deficiencies of conventional wisdom relate to uncritical acceptance of the neo-classical economic model. More attention should be given to dynamic analyses, transportation supply and the inter-relationships between travel demand and transportation supply. The present empirical analysis, concerned with sectoral, spatial and temporal aspects of accessibility to employment within Greater Glasgow, revolves around the first two recommendations. Existing methods of evaluating accessibility/transportation supply are assessed and the cumulative/spatial opportunity model adopted. An on-line analytical framework which calculates, graphs and maps the relevant cumulative opportunity curves and accessibility indices is developed. Decentralisation dominated all the land use patterns (residential and work-place). Individual private transport provision in terms of potential travel times remained approximately constant while individual public transport provision declined significantly. The number of employment opportunities represented an important source of sectoral and temporal variation between and within accessibility distributions. Private transport accessibility was consistently more efficient and equitable than public transport accessibility whilst the advantage of private over public transport accessibility which increased from core to periphery widened through time. At any point in time, differences in efficiency and equity between accessibility distributions were attributable to the respective land use configurations. Only with respect to the equity of public transport accessibility did alternative land use patterns have little or no effect. Through time, efficiency of private transport accessibility remained essentially constant given that the negative effects of land use change approximately balanced the positive effects of changes in transport provision. In contrast, the effects of changes in land use and transport provision upon public transport accessibility were of greater magnitude and reinforced each other, leading to a significant reduction in efficiency. Overall, accessibility to employment became less efficient within Greater Glasgow.
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