手法を比較

	Isolation Index	Gini Coefficient	Index of Dissimilarity
分野	Sociology	Sociology	Sociology
系統	Process / pipeline	Process / pipeline	Process / pipeline
提唱年	1954	1912	1955
提唱者	Wendell Bell (formalization of P* indices)	Corrado Gini	Otis Dudley Duncan & Beverly Duncan
種類	Exposure-dimension segregation index	Scalar measure of statistical dispersion / inequality	Index of evenness of two groups across units
原典	Bell, W. (1954). A probability model for the measurement of ecological segregation. Social Forces, 32(4), 357–364.	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.	Duncan, O. D., & Duncan, B. (1955). A methodological analysis of segregation indexes. American Sociological Review, 20(2), 210–217.
別名	P* isolation index, interaction index, exposure index, Bell isolation index	Gini index, Gini ratio, Gini concentration ratio, G	dissimilarity index, Duncan index, D index, segregation index
関連	5	5	5
概要	The isolation index measures the exposure dimension of segregation: the extent to which members of a minority group are exposed only to one another rather than to members of other groups. It answers the question 'what is the own-group share of the typical neighbor (or classmate, or coworker) that a member of the focal group encounters?' Unlike evenness measures, it depends on the relative size of the group as well as its spatial distribution.	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 index of dissimilarity, often called the Duncan segregation index, measures how unevenly two groups — such as two racial or occupational groups — are distributed across a set of units like neighborhoods, schools, or occupations. It ranges from 0, when both groups have identical distributions across units, to 1, when the units are completely segregated, and has the intuitive interpretation of the share of one group that would have to relocate to achieve an even distribution.