文摘
The M25 London Orbital Motorway has affected levels of accessibility in Britain and this has been discussed in an earlier paper. Changes so caused are thought likely to affect regional development and the objective of this research is to evaluate the nature of this relationship. The methodology involves the construction of a series of measures of both regional development, as the impact or dependent variable, and accessibility, as the policy or control variable. The regressions also include a number of other potential explanatory factors. Accessibility is measured using time, distance and cost impedance functions for heavy goods vehicle movements. The results are somewhat different from those found in previous research involving different spatial and temporal circumstances. During the 1980s places with the highest general levels of accessibility (including that arising from the construction of the M25) score poorest on the changing development indicators. However, when the component of accessibility change which is caused by the actual construction of the M25 motorway is isolated, then it can be demonstrated that such changes are positively related to changing levels of economic development, at least for some impedance functions.