Inequality in Access to Improved Water Source: A Regional Analysis by Theil Index

This study applies Theil’s second measure for looking into inequality in access to improved water source. This index allows inequalities to be broken up within and between groups. An analysis of 188 countries for the period 1990–2012 demonstrates three observations: first, decline in ine-quality in access to improved water source is characterized by both within-group and be-tween-group inequality elements; second, between-group inequalities are at present the key con-tributor of the entire inequality scenario; and lastly, an inclusive study on within-group inequalities divulges the significant role played by Central and South American and Middle East countries towards increase in inequalities and countries pertaining to North America, Asia and Oceania, Af-rica, and Europe towards decline in inequalities.