手法を比較

	Gini Coefficient	Atkinson Index	Lorenz Curve
分野	Sociology	Sociology	Sociology
系統	Process / pipeline	Process / pipeline	Process / pipeline
提唱年	1912	1970	1905
提唱者	Corrado Gini	Anthony Barnes Atkinson	Max Otto Lorenz
種類	Scalar measure of statistical dispersion / inequality	Welfare-based, parameterized inequality index	Graphical representation of distributional inequality
原典	Ceriani, L., & Verme, P. (2012). The origins of the Gini index: extracts from Variabilità e Mutabilità (1912) by Corrado Gini. The Journal of Economic Inequality, 10(3), 421–443.	Atkinson, A. B. (1970). On the measurement of inequality. Journal of Economic Theory, 2(3), 244–263.	Lorenz, M. O. (1905). Methods of measuring the concentration of wealth. Publications of the American Statistical Association, 9(70), 209–219.
別名	Gini index, Gini ratio, Gini concentration ratio, G	Atkinson inequality measure, Atkinson's A, welfare-based inequality index	Lorenz concentration curve, Lorenz diagram, cumulative share curve
関連	5	5	5
概要	The Gini coefficient is the most widely used single-number summary of inequality in a distribution such as income or wealth. Introduced by the Italian statistician Corrado Gini in 1912, it equals twice the area between the Lorenz curve and the line of perfect equality, ranging from 0 when everyone has the same amount to a maximum approaching 1 when one unit holds everything.	The Atkinson index is a welfare-based measure of inequality that incorporates an explicit, analyst-chosen parameter for how much society dislikes inequality. Introduced by Anthony Atkinson in 1970, it asks what fraction of total income could be discarded, under an equal distribution, while leaving social welfare unchanged — making the ethical judgement behind any inequality comparison transparent rather than hidden.	The Lorenz curve is a graphical device that displays the full shape of inequality in a distribution by plotting the cumulative share of a quantity (such as income) held by the cumulative share of the population, ranked from poorest to richest. Introduced by Max Lorenz in 1905, it underlies the Gini coefficient and provides the basis for ranking distributions by inequality when one curve lies entirely above another.