Abstract
Confusion in the literature between the concepts of internal consistency and homogeneity has led to a misuse of coefficient alpha as an index of item homogeneity. Coefficient alpha is actually a complexly determined test statistic, item homogeneity only being one influence on its magnitude. The related statistic, the average intercorrelation, has similar difficulties. Several indices of item homogeneity derived from the model of common factor analysis are offered as alternatives.
Keywords
Homogeneity (statistics)StatisticStatisticsConfusionInternal consistencyMathematicsTest statisticEconometricsPsychologyPsychometricsStatistical hypothesis testing
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Publication Info
- Year
- 1977
- Type
- article
- Volume
- 37
- Issue
- 4
- Pages
- 827-838
- Citations
- 517
- Access
- Closed
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Cite This
Samuel B. Green,
Robert W. Lissitz,
Stanlen A. Mulaik
(1977).
Limitations of Coefficient Alpha as an Index of Test Unidimensionality1.
Educational and Psychological Measurement
, 37
(4)
, 827-838.
https://doi.org/10.1177/001316447703700403
Identifiers
- DOI
- 10.1177/001316447703700403