Household Water Demand Estimation

This working paper addresses the issues: 1) whether there is a simultaneous equations problem when estimating demand for water with multipart rate schedules and, if there is one, what techniques should be used to correct for it; and 2) whether average or marginal price is the relevant measure in estimating the demand function. In addition, the issue is raised of sample selection bias in a rate schedule, combined with a fixed charge for consumption below the level where a block rate tariff per unit consumed. This study uses results from a sample of 685 families from 34 localities in rural Argentina (taken in 1987) and presents an analysis of the results with different estimation techniques.