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Supersizing effect sizes raises concerns: a reply to Zimmerman (2014).
M Brent Donnellan1, Christopher J Ferguson2
1Department of Psychology, Michigan State University.
Developmental Psychology
|January 8, 2014
Summary
This study clarifies motivations for reanalysis and demonstrates that further age-based analyses do not alter conclusions. Scientists should exercise caution when reporting effect sizes, as emerging research supports our interpretations.
Area of Science:
- Scientific methodology
- Statistical analysis
- Research interpretation
Background:
- A previous reanalysis was suggested to add little to the scientific literature.
- Disagreement exists regarding the interpretation of effect sizes and their reporting.
Purpose of the Study:
- To clarify the motivations behind a reanalysis of existing scientific literature.
- To address criticisms regarding the contribution of the reanalysis to the field.
- To emphasize the importance of cautious reporting of effect sizes.
Main Methods:
- Reanalysis of existing data.
- Exploration of age-related factors in data interpretation.
- Comparison of current interpretations with emerging experimental literature.
Main Results:
- Further analyses, including age-related considerations, did not change the original conclusions.
- The authors' interpretations are supported by nascent experimental literature.
- A discrepancy was noted between the authors' findings and Zimmerman's (2014) suggestions.
Conclusions:
- The reanalysis provides a valuable contribution to the scientific literature.
- Scientists are advised to maintain caution when describing effect sizes.
- Emerging experimental evidence aligns with the authors' interpretive framework.
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