Cronbach's alpha

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In psychometrics, a reliability coefficient indicating the degree of internal consistency of items within a test. Mathematically, it is the equivalent of the average of all possible split-half reliability coefficients of the test. If certain assumptions are met, it ranges from 0 (zero internal consistency) to 1 (perfect internal consistency); a negative alpha coefficient indicates that items of the scale are negatively correlated and that an inappropriate reliability model is being used. Also called alpha reliability coefficient and coefficient alpha. See also Kuder-Richardson coefficient. [Named after the US psychologist Lee J(oseph) Cronbach (1916–2001), who introduced it in Psychometrika in 1951, and alpha (α) the first letter of the Greek alphabet, which symbolizes it]

Subjects: Psychology.

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