Method evidence record
Effect Size in Education Research
An effect size is a standardized, scale-free measure of the magnitude of a difference or relationship — how big an effect is, not just whether it is statistically significant. In education research it is the common currency for reporting intervention impacts and for combining studies in meta-analysis, with the standardized mean difference (Cohen's d, or its bias-corrected form Hedges' g) the most familiar. Effect sizes let researchers compare effects across studies, outcomes, and scales, and translate statistical results into terms practitioners can weigh.
Evidence statusSources recorded, not reviewedBibliographic sources are present. Claim-level evidence review has not been performed.
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Recorded
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Effect Sizes for Quantifying and Synthesizing Educational Interventions
Taxonomic method recordprocess-pipelineeducation
Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences (2nd ed.). Lawrence Erlbaum Associates. · ISBN 9780805802832
Open full method2 recorded citations, copied from the method source record.
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Related methods
Suggested2
Generated from the method graph and shown as machine-suggested relations. No evidence claim is inferred.
- Same method familyEffect Size
machine-suggestedRelational suggestion, not evidence.
- Same method familyWhat Works Clearinghouse Standards
machine-suggestedRelational suggestion, not evidence.