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Effect Size

Statistics & analysis

Definition

A standardised measure of the magnitude of a relationship or difference (e.g. Cohen's d, r), reported alongside statistical significance.

Where it's used

  • Judging whether a significant result is practically meaningful
  • Power analysis for sample-size planning
  • Pooling results in meta-analysis

Software used

SPSSRG*Power

Related concepts

p-valueSample SizeMeta-analysisANOVAAverage Variance Extracted (AVE)Bootstrapping
Read the complete guide A–Z encyclopedia

Guides that use this concept

All guides

What is Meta-Analysis? Pooling Evidence the Right Way

2 min read

Understanding P-Values and Statistical Significance (Plainly)

1 min read

Qualitative vs Quantitative vs Mixed Methods: Which Fits Your Study?

1 min read

Reliability and Validity Explained (With Examples)

1 min read
Mentoring for this area:Questionnaire DesignSamplingSPSS

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