Gyimesi, M. L., Webersberger, V., Del Giudice, M., Voracek, M., & Tran, U. (2025).
One app to rule them all: A one-stop calculator and guide for 95 effect-size variants for two-group comparisons of central tendency, variability, overlap, dominance, and distributional tails.
Advances in Methods and Practices in Psychological Science, 8, 1-37.
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Link: Companion app

Del Giudice, M. (2024).
g-Disattenuation: Using omega coefficients to estimate effect sizes for the underlying general factors.
Preprint. DOI:10.31234/osf.io/zutrx
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Supplementary material: Code and data

Del Giudice, M. (2024).
Statistical indices of masculinity-femininity: A theoretical and practical framework.
Behavior Research Methods.
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Supplementary material: Online supplement; R function for M-F indices and plots; code and data

Del Giudice, M. (2024).
The prediction-explanation fallacy: A pervasive problem in scientific applications of machine learning.
Methodology, 20, 22-46.
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Del Giudice, M. (2024).
Data matrix disattenuation: A simple, effective method for correcting measurement error in multivariate datasets.
Preprint. DOI:10.31234/osf.io/9kaw6
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Supplementary material: R function for data matrix disattenuation

Del Giudice, M. (2023).
Relative density clouds: Visualizing and exploring multivariate patterns of group differences.
PLoS ONE, 18, e0287784.
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Supplementary material: Online supplement; R function for relative density clouds; code and data

Del Giudice, M. (2023).
Individual and group differences in multivariate domains: What happens when the number of traits increases?
Personality and Individual Differences, 213, 112282.
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Supplementary material: Online supplement

Del Giudice, M. (2023).
[Comment] Arbitrary, inappropriate grading criteria distort the evaluation of evidence: A comment on Kim et al.’s (2022) umbrella review.
Neuroscience and Biobehavioral Reviews, 147, 105089.
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Del Giudice, M. (2023).
The S-index: Summarizing patterns of sex differences at the distribution extremes.
Personality and Individual Differences, 205, 112088.
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Supplementary material: Online supplement; R function for the S-index; code and data

Del Giudice, M., & Gangestad, S. W. (2023).
[Comment] No evidence against the greater male variability hypothesis:
A commentary on Harrison et al.’s meta-analysis of animal personality.
Evolutionary Psychological Science.
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Del Giudice, M., & Gangestad, S. W. (2022).
Hormone ratios suffer from striking lack of robustness to measurement error.
Psychoneuroendocrinology, 142, 105802.
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Supplementary material: Supporting online material; code and data

Del Giudice, M. (2022).
The square-root scree plot: A simple improvement to a classic display.
OpenPsych, DOI:10.26775/OP.2022.11.19
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Del Giudice, M. (2022).
Measuring sex differences and similarities.
In D. P. VanderLaan & W. I. Wong (Eds.), Gender and sexuality development: Contemporary theory and research.
New York: Springer.
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Supplementary material: R functions for Mahalanobis D; Excel calculator

Del Giudice, M. (2021).
[Comment] Binary thinking about the sex binary: A comment on Joel (2021).
Neuroscience and Biobehavioral Reviews, 127, 144-145.
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Del Giudice, M. (2021).
Are we comparing apples or squared apples? The proportion of explained variance exaggerates differences between effects.
OpenPsych. DOI:10.26775/OP.2021.06.15
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Del Giudice, M. (2021).
Effective dimensionality: A tutorial.
Multivariate Behavioral Research, 56, 527-542.
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Supplementary material: R function for ED estimation; Data and analysis script

Del Giudice, M. (2021).
[Comment] Are complex causal models less likely to be true than simple ones? A critical comment on Trafimow (2017).
Behavior Research Methods, 53, 1077-1080.
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Del Giudice, M., & Gangestad, S. W. (2021).
A traveler’s guide to the multiverse: Promises, pitfalls, and a framework for the evaluation of analytic decisions.
Advances in Methods and Practices in Psychological Science, 4, 1-15.
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Supplementary material: Supplement; Code, data, and analysis script

Del Giudice, M. (2018).
Addendum to: Heterogeneity coefficients for Mahalanobis’ D as a multivariate effect size.
Multivariate Behavioral Research, 53, 571-573.
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Supplementary material: R functions for Mahalanobis D

Del Giudice, M. (2017).
Heterogeneity coefficients for Mahalanobis’ D as a multivariate effect size.
Multivariate Behavioral Research, 52, 216-221.
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Supplementary material: R functions for Mahalanobis D

Del Giudice, M. (2017).
Statistical tests of differential susceptibility: Performance, limitations, and improvements.
Development and Psychopathology, 29, 1267-1278.
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Del Giudice, M., Lippa, R. A., Puts, D. A., Bailey, D. H., Bailey, J. M., & Schmitt, D. P. (2015).
[Online document] Mosaic brains? A methodological critique of Joel et al. (2015).
DOI: 10.13140/RG.2.1.1038.8566.
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Del Giudice, M. (2013).
Multivariate misgivings: Is D a valid measure of group and sex differences?
Evolutionary Psychology, 11, 1067-1076.
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Del Giudice, M. (2009).
On the real magnitude of psychological sex differences.
Evolutionary Psychology, 7, 264-279.
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Supplementary material: R functions for Mahalanobis D; Excel calculator