Method evidence record

Effect Size

Effect size quantifies the magnitude of a research finding independent of sample size. While a p-value tells you whether a result is statistically significant, an effect size tells you how big the result is. Jacob Cohen formalized effect size measurement in behavioral sciences (1988), establishing standard benchmarks (small = 0.2, medium = 0.5, large = 0.8 for Cohen's d). Effect sizes are essential for meta-analysis, power analysis, and communicating the practical importance of research findings.

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Effect Size: Quantifying the Magnitude of Research Findings

Taxonomic method record · process-pipeline / research-statistics

Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences (2nd ed.). Lawrence Erlbaum Associates. · ISBN 0-8058-0283-5
Cumming, G. (2012). Understanding the New Statistics: Effect Sizes, Confidence Intervals, and Meta-Analysis. Routledge. · ISBN 0-415-87968-8
Lakens, D. (2013). Calculating and Reporting Effect Sizes to Facilitate Cumulative Science: A Practical Primer for t-Tests and ANOVAs. Frontiers in Psychology, 4, 863. · DOI 10.3389/fpsyg.2013.00863

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Same method familyConfidence Intervalmachine-suggested · Relational suggestion, not evidence.Same method familyP-Value and Statistical Significancemachine-suggested · Relational suggestion, not evidence.Same method familyStatistical Power and Sample Sizemachine-suggested · Relational suggestion, not evidence.Same method familyType I and Type II Errorsmachine-suggested · Relational suggestion, not evidence.