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ERIC Number: EJ782467
Record Type: Journal
Publication Date: 2007-Mar
Pages: 22
Abstractor: Author
Reference Count: 27
ISSN: ISSN-1076-9986
Approximate Confidence Intervals for Standardized Effect Sizes in the Two-Independent and Two-Dependent Samples Design
Viechtbauer, Wolfgang
Journal of Educational and Behavioral Statistics, v32 n1 p39-60 Mar 2007
Standardized effect sizes and confidence intervals thereof are extremely useful devices for comparing results across different studies using scales with incommensurable units. However, exact confidence intervals for standardized effect sizes can usually be obtained only via iterative estimation procedures. The present article summarizes several closed-form approximations to the exact confidence interval bounds in the two-independent and two-dependent samples design. Monte Carlo simulations were conducted to determine the accuracy of the various approximations under a wide variety of conditions. All methods except one provided accurate results for moderately large sample sizes and converged to the exact confidence interval bounds as sample size increased. (Contains 6 tables and 3 figures.)
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A