手法を比較

	Theil Segregation Index	Atkinson Index
分野	Sociology	Sociology
系統	Process / pipeline	Process / pipeline
提唱年	1971	1970
提唱者	Henri Theil & Anthony Finizza	Anthony Barnes Atkinson
種類	Entropy-based multigroup segregation index	Welfare-based, parameterized inequality index
原典	Theil, H., & Finizza, A. J. (1971). A note on the measurement of racial integration of schools by means of informational concepts. Journal of Mathematical Sociology, 1(2), 187–193.	Atkinson, A. B. (1970). On the measurement of inequality. Journal of Economic Theory, 2(3), 244–263.
別名	Theil's H, information theory index, entropy segregation index, multigroup entropy index	Atkinson inequality measure, Atkinson's A, welfare-based inequality index
関連	5	5
概要	Theil's information index, denoted H, is an entropy-based measure of segregation that, unlike the two-group dissimilarity index, handles any number of groups at once. It compares the diversity (entropy) found within each unit to the diversity of the whole population: segregation is high when units are internally homogeneous even though the overall population is diverse. Its defining virtue is exact decomposability across nested levels and across groups.	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.