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ERIC Number: EJ782420
Record Type: Journal
Publication Date: 2007
Pages: 28
Abstractor: Author
Reference Count: 35
ISSN: ISSN-0162-3737
Intraclass Correlation Values for Planning Group-Randomized Trials in Education
Hedges, Larry V.; Hedberg, E. C.
Educational Evaluation and Policy Analysis, v29 n1 p60-87 2007
Experiments that assign intact groups to treatment conditions are increasingly common in social research. In educational research, the groups assigned are often schools. The design of group-randomized experiments requires knowledge of the intraclass correlation structure to compute statistical power and sample sizes required to achieve adequate power. This article provides a compilation of intraclass correlation values of academic achievement and related covariate effects that could be used for planning group-randomized experiments in education. It also provides variance component information that is useful in planning experiments involving covariates. The use of these values to compute the statistical power of group-randomized experiments is illustrated. (Contains 11 tables.)
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: Elementary Secondary Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Identifiers - Assessments and Surveys: Comprehensive Tests of Basic Skills; Early Childhood Longitudinal Survey
IES Cited: ED511782; ED503448; ED511789