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ERIC Number: ED530373
Record Type: Non-Journal
Publication Date: 2012
Pages: 5
Abstractor: ERIC
Reference Count: N/A
A D-Estimator for Single-Case Designs
Shadish, William; Hedges, Larry; Pustejovsky, James; Rindskopf, David
Society for Research on Educational Effectiveness
Over the last 10 years, numerous authors have proposed effect size estimators for single-case designs. None, however, has been shown to be equivalent to the usual between-groups standardized mean difference statistic, sometimes called d. The present paper remedies that omission. Most effect size estimators for single-case designs use the within-person variance as the standardization factor for the effect size. But in the usual between-groups study, like a randomized experiment, the between-person variance is the standardization factor. Taking advantage of the fact that most studies that use single-case design methodology report results from more than one case, the authors show how a d-statistic can be developed that is equivalent to the between-groups estimator. The new d-estimator is complex, requiring knowledge of the autocorrelation, the within-person variability, and the between-person variability.
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Publication Type: Reports - Descriptive
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: Society for Research on Educational Effectiveness (SREE)