Inequality measures for location problems

The paper considers the measurement of inequality in the distribution of distances between the users and the facility to be located. It provides a general framework for quantifying inequality, which is based on the notion of proximity between a proposed solution and a set of ideal solutions. Many inequality measures used in the location literature (and some that have not been used) can be derived from this general framework. The paper presents some fundamental axioms for the measurement of inequality, and shows that only two of the measures considered satisfy these axioms. As a result of a computational experiment, it finds that there is considerable agreement (as to which is the best) between these two measures, however, the agreement is not complete. The paper discusses reasons for disagreements, and properties of these measures when applied to location problems. It provides some practical suggestions for modeling inequality in a location problem and gives directions for future research.