Combining reliability coefficients: possible application to meta-analysis and reliability generalization
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Published on: September 27, 2019
1Department of Veterans Affairs, VA Long Beach Healthcare Systems, California 90822, USA.
Abstract:
Formulae for combining reliability coefficients from any number of samples are provided. These formulae produce the exact reliability one would compute if one had the raw data from the samples. Needed are the sample means, standard deviations, sample sizes, and reliability coefficients. The formulae work for coefficient alpha, KR-20, retest, alternate-forms, split-half, interrater (intraclass), Gilmer-Feldt, Angoff-Feldt, validity, and other coefficients. They may be particularly useful for meta-analytic and reliability generalization studies.
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