Commuting economy : an alternative approach for assessing regional commuting efficiency

This paper revisits the notion of random commuting within the excess commuting framework. In doing so, it argues that the average random commute, is a more appropriate basis for measuring the efficiency of urban commuting patterns. Using this as a base, the paper introduces two new measures of commuting efficiency based on measuring the collective commuting economy of individuals for the journey to work: commuting economy and normalised commuting economy. It is argued that because the average random commute has an intrinsically behavioural interpretation, the measures introduced yield more explicit explanations of the overall nature of travel behaviour within the constraints set by land use geography and the spatial distribution of the transport network. The framework is applied for two different years, 1991 and 2001, and for different modes of transport. The results show that the average actual commute has moved further away from the average random commute, implying that greater intermixing of residential and employment functions has led to more efficient commuting behaviour.