Compare methods

	Index of Dissimilarity	Social Mobility Table
Field	Sociology	Sociology
Family	Process / pipeline	Process / pipeline
Year of origin	1955	1927 (concept); 1970s–1980s (modern analysis)
Originator	Otis Dudley Duncan & Beverly Duncan	Pitirim Sorokin; refined by Hauser, Hout, Featherman
Type	Index of evenness of two groups across units	Cross-classification of social origins by destinations
Seminal source	Duncan, O. D., & Duncan, B. (1955). A methodological analysis of segregation indexes. American Sociological Review, 20(2), 210–217.	Hauser, R. M. (1978). A structural model of the mobility table. Social Forces, 56(3), 919–953.
Aliases	dissimilarity index, Duncan index, D index, segregation index	mobility table, intergenerational mobility table, origin-destination table, transition table analysis
Related	5	5
Summary	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.	A social mobility table is a cross-classification of individuals by their social origin (typically a parent's class or occupation) and their own destination class, forming the empirical foundation of intergenerational mobility research. Analyzing it separates how much people move between classes, distinguishes movement forced by changing class sizes from genuine exchange, and isolates the underlying origin–destination association that measures the openness of a society.