Is low coverage of modern infrastructure services in African cities due to lack of demand or lack of supply?

The aim of this paper is to show how to measure the contributions of both demand and supply-side obstacles to better coverage of infrastructure services using household survey data. Some households may live in an area where there is access to the service, but may still be located too far from the water pipe to be able to be connected. This paper suggests how, to some extent, this type of biases can be dealt with by using regression techniques and shows that using an econometric as opposed to a statistical approach to the estimation can make a significant difference in the results. Section 2 of the paper describes and formalizes in simple mathematical notations the methodology for assessing the relative role of demand and supply-side problems to explain lack of coverage of modern infrastructure services. Results obtained with this methodology for African countries in the case of urban coverage of piped water are then provided. The next section presents an alternative econometric approach to assessing the magnitude of demand and supply-side constraints to coverage, as well as the results obtained from this alternative method