Equity Measures for Irrigation Performance Evaluation

ABSTRACT

This paper deals with the analytical issues involved in developing and using practical measures of equity for irrigation project performance evaluation. Deriving from the economic literature on equity in income distribution, the paper discusses the usefulness of seven different axioms for equity measures in evaluating the robustness of seven different positive measures of equity such as the range, the relative mean deviation, the variance, the coefficient of variation, the standard deviation of logarithms, the Gini coefficient and Theil's information measure. Based on the fulfillment/non-fulfillment of different axioms, the paper discusses the relative merits/demerits of the above-mentioned seven different measures and concludes on the basis of this critical evaluation that Theil's information measure is more useful than the rest since it fulfills many of the important axioms in addition to its being amenable for decomposition analysis.