Appendix
Figure A.1: The Quantile Functions of Urban Per Capita Expenditure, Georgia 600
Quantile
480
360
240
120
0 0
0.2
0.4
0.6
0.8
1.0
Expenditure percentile 2003
2006
Source: Based on ADePT Poverty and Inequality modules using Integrated Household Survey of Georgia 2003 and 2006.
axis reports percentiles. A quantile function reports the level below which per capita expenditure falls for a given population percentage, when the population is ranked by per capita expenditure. The solid line represents the quantile function for 2003, and the dotted line corresponds to the urban distribution of consumption expenditure for 2006. The horizontal lines are poverty lines for 2003 and 2006. If a distribution’s quantile function lies completely above that of another distribution, then the situation is called first-order stochastic dominance. When a distribution first-order stochastically dominates another distribution, then every income standard reported ranks the former distribution better than the latter distribution. If two quantile functions cross each other, then a dominance relationship may not hold and ranking distributions would depend on the particular per capita expenditure standards used. The curve with the solid line represents Georgia’s urban quantile function in 2003, and the quantile function with the dotted line corresponds to Georgia in 2006. If a quantile function lies completely above another
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