Excess commuting: a critical review and comparative analysis of concepts, indices, and policy implications

The last three decades have witnessed substantial growth in the literature on excess commuting. Researchers have proposed and applied a number of commuting benchmarks and excess commuting indices that aim to evaluate the commuting efficiency and jobs-housing balance of cities. A comprehensive review and comparative evaluation of the proposed metrics in terms of their ability to capture the intended phenomena, while controlling for the other general characteristics of cities, has yet to be performed. This article attempts to fill this gap by examining four commuting benchmarks (minimum commute, maximum commute, random commute, and proportionally matched commute) and five excess commuting indices (excess commute, commuting potential utilized, commuting economy, normalized commuting economy, and effort). Our conceptual analysis of the indices is complemented with a comparative empirical analysis of commuting in thirty Canadian cities. We explore relationships between the indices and point out the strengths and limitations of each. The findings suggest that no single index can adequately capture the commuting performance of an urban area, while each index can be employed to address a specific policy question. Used together, the indices can provide a reasonably good understanding of urban form and commuting behavior.