Z-curve
@replicationindex.com
MetaScience, MetaScientist, MetaPsycholog, UberScientist
Pinned
Z-curve
@replicationindex.com
· 21d
Personality Science 2025 – The Science of Human Diversity - Replicability-Index
Table of Content Why I Wrote My Own Textbook on Personality Psychology When I first started teaching Introduction to Personality Psychology (PSY230) at the University of Toronto Mississauga in 2001, m...
replicationindex.com
A new textbook:
- German style in English
- no p-hacked, bullshit stories
- quantifying claims
- taking measurement seriously
- unapologetically making supported causal claims
- open to feedback and corrections
replicationindex.com/2020/08/19/p...
- German style in English
- no p-hacked, bullshit stories
- quantifying claims
- taking measurement seriously
- unapologetically making supported causal claims
- open to feedback and corrections
replicationindex.com/2020/08/19/p...
Zen Philosophy of Science:
Science is supposed to be self-correcting.
Scientists are invested in their ideas, publication, etc.
If science corrects itself and no scientists' feelings get hurt, did it actually happen?
Science is supposed to be self-correcting.
Scientists are invested in their ideas, publication, etc.
If science corrects itself and no scientists' feelings get hurt, did it actually happen?
December 3, 2025 at 5:49 PM
Zen Philosophy of Science:
Science is supposed to be self-correcting.
Scientists are invested in their ideas, publication, etc.
If science corrects itself and no scientists' feelings get hurt, did it actually happen?
Science is supposed to be self-correcting.
Scientists are invested in their ideas, publication, etc.
If science corrects itself and no scientists' feelings get hurt, did it actually happen?
25 years of research to see whether the race IAT predict racially biased behaviors without any success.
Maybe it is time to study what actually predicts racial biases in the real world!
For White researchers to use the social relevance of racism to advance careers is racist itself.
Maybe it is time to study what actually predicts racial biases in the real world!
For White researchers to use the social relevance of racism to advance careers is racist itself.
December 3, 2025 at 4:53 PM
25 years of research to see whether the race IAT predict racially biased behaviors without any success.
Maybe it is time to study what actually predicts racial biases in the real world!
For White researchers to use the social relevance of racism to advance careers is racist itself.
Maybe it is time to study what actually predicts racial biases in the real world!
For White researchers to use the social relevance of racism to advance careers is racist itself.
This an open invitation for @jordanaxt.bsky.social to participate in an adversarial collaboration to model these data without confirmation bias. I see no evidence that the race IAT measures anything implicit that is not reflected in self-ratings.
replicationindex.com/2025/12/02/i...
replicationindex.com/2025/12/02/i...
December 3, 2025 at 4:05 PM
This an open invitation for @jordanaxt.bsky.social to participate in an adversarial collaboration to model these data without confirmation bias. I see no evidence that the race IAT measures anything implicit that is not reflected in self-ratings.
replicationindex.com/2025/12/02/i...
replicationindex.com/2025/12/02/i...
Scientific utopia. @briannosek.bsky.social responds to my criticism of the IAT (LOL) Sometimes silence says more than a thousand words.
replicationindex.com/2025/12/02/i...
replicationindex.com/2025/12/02/i...
Is the Implicit Association Test Too Big To Fail? - Replicability-Index
The Implicit Association Test (IAT) was introduced in the late 1990s as a measure of implicit associations, cognitions, and attitudes that might not be fully captured by self-report measures. The pros...
replicationindex.com
December 3, 2025 at 4:01 PM
Scientific utopia. @briannosek.bsky.social responds to my criticism of the IAT (LOL) Sometimes silence says more than a thousand words.
replicationindex.com/2025/12/02/i...
replicationindex.com/2025/12/02/i...
Political ideology distorts interpretation of science.
Yes, there are genetic influences on behavior.
No, that does not mean that some people are better than others.
Genetic variability exists because nature thought it is fine (it did not hurt evo. fitness).
Eugenics is man-made dogma.
Yes, there are genetic influences on behavior.
No, that does not mean that some people are better than others.
Genetic variability exists because nature thought it is fine (it did not hurt evo. fitness).
Eugenics is man-made dogma.
Also, eugenics has no scientific basis at all. Just genetically misinterpreted and p-hacked twin studies, and 60 years of failure to discover causal “genes for behavior.”
December 3, 2025 at 3:56 PM
Political ideology distorts interpretation of science.
Yes, there are genetic influences on behavior.
No, that does not mean that some people are better than others.
Genetic variability exists because nature thought it is fine (it did not hurt evo. fitness).
Eugenics is man-made dogma.
Yes, there are genetic influences on behavior.
No, that does not mean that some people are better than others.
Genetic variability exists because nature thought it is fine (it did not hurt evo. fitness).
Eugenics is man-made dogma.
Reposted by Z-curve
How many failed attempts to show that the IAT measures something of importance do we need?
replicationindex.com/2025/12/02/i...
replicationindex.com/2025/12/02/i...
Is the Implicit Association Test Too Big To Fail? - Replicability-Index
The Implicit Association Test (IAT) was introduced in the late 1990s as a measure of implicit associations, cognitions, and attitudes that might not be fully captured by self-report measures. The pros...
replicationindex.com
December 2, 2025 at 10:13 PM
How many failed attempts to show that the IAT measures something of importance do we need?
replicationindex.com/2025/12/02/i...
replicationindex.com/2025/12/02/i...
What have we learned?
1. All measures measure a single construct. No evidence that implicit measures like the IAT measure anything distinct (Schimmack, 2020).
2. Self-report measures are much more valid than implicit measures like the IAT.
3. Time to tell Project Implicit visitors about this.
1. All measures measure a single construct. No evidence that implicit measures like the IAT measure anything distinct (Schimmack, 2020).
2. Self-report measures are much more valid than implicit measures like the IAT.
3. Time to tell Project Implicit visitors about this.
December 2, 2025 at 4:45 PM
What have we learned?
1. All measures measure a single construct. No evidence that implicit measures like the IAT measure anything distinct (Schimmack, 2020).
2. Self-report measures are much more valid than implicit measures like the IAT.
3. Time to tell Project Implicit visitors about this.
1. All measures measure a single construct. No evidence that implicit measures like the IAT measure anything distinct (Schimmack, 2020).
2. Self-report measures are much more valid than implicit measures like the IAT.
3. Time to tell Project Implicit visitors about this.
A better fitting model shows no discriminant validity for any set of measures (implicit, explicit, behavioral). A single attitude best measured with self-ratings. Prejudice is real, people know it, and report it. Time to study racism, not laboratory tasks.
December 2, 2025 at 4:35 PM
A better fitting model shows no discriminant validity for any set of measures (implicit, explicit, behavioral). A single attitude best measured with self-ratings. Prejudice is real, people know it, and report it. Time to study racism, not laboratory tasks.
"From a more optimistic lens, these results could be viewed as encouraging for the predictive validity and utility of indirect measures. "
LOL where are the adversarial voices here?
EPT and AMP: over 90% of the variance is ERROR
So, they cannot have predictive validity.
IAT .57 * .16 * .62 = .06!
LOL where are the adversarial voices here?
EPT and AMP: over 90% of the variance is ERROR
So, they cannot have predictive validity.
IAT .57 * .16 * .62 = .06!
Implicit racial attitudes accounted for ~2.5% of variance in behavior beyond explicit racial attitudes, an effect size that was *just* over our agreed upon threshold for what would constitute a practically significant effect. Explicit racial attitudes still explained much more variance (~45%).
December 2, 2025 at 3:27 PM
"From a more optimistic lens, these results could be viewed as encouraging for the predictive validity and utility of indirect measures. "
LOL where are the adversarial voices here?
EPT and AMP: over 90% of the variance is ERROR
So, they cannot have predictive validity.
IAT .57 * .16 * .62 = .06!
LOL where are the adversarial voices here?
EPT and AMP: over 90% of the variance is ERROR
So, they cannot have predictive validity.
IAT .57 * .16 * .62 = .06!
I think this is a much more informative figure to share.
1. Implicit to disposition (not behavior) b = .05 to .27
2. No convergent validity for Implict measures
(eval. prime = .08, AMP = .25)
3. Implicit factor = IAT without random error.
1. Implicit to disposition (not behavior) b = .05 to .27
2. No convergent validity for Implict measures
(eval. prime = .08, AMP = .25)
3. Implicit factor = IAT without random error.
December 2, 2025 at 3:22 PM
I think this is a much more informative figure to share.
1. Implicit to disposition (not behavior) b = .05 to .27
2. No convergent validity for Implict measures
(eval. prime = .08, AMP = .25)
3. Implicit factor = IAT without random error.
1. Implicit to disposition (not behavior) b = .05 to .27
2. No convergent validity for Implict measures
(eval. prime = .08, AMP = .25)
3. Implicit factor = IAT without random error.
For the record. I was never asked to participate in this adversarial collaboration. Maybe I am too adversarial for collaboration, but I am happy that this study was conducted. I also like the title, no implication that IAT measures implicit constructs. Maybe Project Implicit will take note.
New paper in press at JPSP! An adversarial collaboration focusing on a large-scale test of how strongly implicit racial attitudes predict discriminatory behavior. Pre-print here: osf.io/preprints/ps...
December 2, 2025 at 3:12 PM
For the record. I was never asked to participate in this adversarial collaboration. Maybe I am too adversarial for collaboration, but I am happy that this study was conducted. I also like the title, no implication that IAT measures implicit constructs. Maybe Project Implicit will take note.
Reposted by Z-curve
We just preprinted a huge meta-meta-analysis examining the effects of exercise on cognition, memory, and executive function
In short
- 2239 effect sizes
- extreme between-study heterogeneity
- extensive publication bias
- some subgroup/exercise-specific effects
More below (doi.org/10.31234/osf...)
In short
- 2239 effect sizes
- extreme between-study heterogeneity
- extensive publication bias
- some subgroup/exercise-specific effects
More below (doi.org/10.31234/osf...)
OSF
doi.org
December 1, 2025 at 4:19 PM
We just preprinted a huge meta-meta-analysis examining the effects of exercise on cognition, memory, and executive function
In short
- 2239 effect sizes
- extreme between-study heterogeneity
- extensive publication bias
- some subgroup/exercise-specific effects
More below (doi.org/10.31234/osf...)
In short
- 2239 effect sizes
- extreme between-study heterogeneity
- extensive publication bias
- some subgroup/exercise-specific effects
More below (doi.org/10.31234/osf...)
Thanksgiving is over. No more fake smiles left? Enjoy sone open and honest truth.
December 1, 2025 at 2:25 AM
Thanksgiving is over. No more fake smiles left? Enjoy sone open and honest truth.
A positive response to the validation crisis. Systematically reviewing psychometric properties; here measures of prejudice.
osf.io/preprints/ps...
osf.io/preprints/ps...
OSF
osf.io
November 29, 2025 at 7:51 PM
A positive response to the validation crisis. Systematically reviewing psychometric properties; here measures of prejudice.
osf.io/preprints/ps...
osf.io/preprints/ps...
Not sure who cares, but Project Implicit continues to give people useless feedback without any information about measurement error and the invalidity of IATs. Apparently, Harvard does not have to follow rules of ethical use of psychometric tests.
replicationindex.com/2025/11/28/w...
replicationindex.com/2025/11/28/w...
Why You Should Not Trust Your Project Implicit Feedback - Replicability-Index
Project Implicit’s IAT feedback provides users with categorical interpretations of their supposed implicit (outside of awareness) attitudes or mental-health-relevant traits (e.g., prejudice, depressio...
replicationindex.com
November 29, 2025 at 5:18 AM
Not sure who cares, but Project Implicit continues to give people useless feedback without any information about measurement error and the invalidity of IATs. Apparently, Harvard does not have to follow rules of ethical use of psychometric tests.
replicationindex.com/2025/11/28/w...
replicationindex.com/2025/11/28/w...
Reposted by Z-curve
Watch this video before you do your Black Friday shopping on Amazon.
November 28, 2025 at 2:11 PM
Watch this video before you do your Black Friday shopping on Amazon.
Against Agreeabless
www.theguardian.com/lifeandstyle...
www.theguardian.com/lifeandstyle...
How do I respond to someone who says ‘I’m not racist, but ... ’? | Leading questions
It’s important to express your disagreement: for their sake as much as yours, writes advice columnist Eleanor Gordon-Smith. But first decide on what you aim to accomplish
www.theguardian.com
November 28, 2025 at 1:32 PM
Against Agreeabless
www.theguardian.com/lifeandstyle...
www.theguardian.com/lifeandstyle...
Reposted by Z-curve
Preregistrations without Code do not Prevent P-Hacking: You can increase your chances for a significant finding in the absence of real effects even with correlations and t test despite having preregistered your hypothesis (e.g., simply changing arguments in the functions).
doi.org/10.31222/osf...
doi.org/10.31222/osf...
November 25, 2025 at 12:33 PM
Preregistrations without Code do not Prevent P-Hacking: You can increase your chances for a significant finding in the absence of real effects even with correlations and t test despite having preregistered your hypothesis (e.g., simply changing arguments in the functions).
doi.org/10.31222/osf...
doi.org/10.31222/osf...
Reposted by Z-curve
#AcademicSky #PsycSciSky #Metascience
How psychologists handle sampling, measurement, & statistical test assumptions
How psychologists handle sampling, measurement, & statistical test assumptions
November 25, 2025 at 1:38 PM
#AcademicSky #PsycSciSky #Metascience
How psychologists handle sampling, measurement, & statistical test assumptions
How psychologists handle sampling, measurement, & statistical test assumptions
Á position for an über-psychologist in Germany.
Job opportunity — Junior Professorship in Psychological Metascience @zpid.bsky.social leibniz-psychology.onlyfy.jobs/job/10kku5n7 h/t @bethclarke.bsky.social
November 26, 2025 at 5:07 AM
Á position for an über-psychologist in Germany.
Reposted by Z-curve
A device looks impressive, but we forget they simplify reality. Eye-tracking shows where people look, but not what they think. AI can summarize medical symptoms, but it cannot read uncertainty or context. The danger is not “bad technology” but blind trust in its outputs.
#SciWri
#metasci
#SciWri
#metasci
November 22, 2025 at 11:51 AM
Reposted by Z-curve
come on we already went through the replication crisis
When pregnant woman boarded a subway car, 38% of the time someone offered her a seat. If someone dressed as Batman was also in the car it rose to 68%.
phys.org/news/2025-11...
phys.org/news/2025-11...
The Batman effect: The mere sight of the 'superhero' can make us more altruistic
If "Batman" appears on the scene, we immediately become more altruistic: in fact, research conducted by psychologists from the Università Cattolica del Sacro Cuore, Milan, shows that the sudden appear...
phys.org
November 22, 2025 at 1:13 AM
come on we already went through the replication crisis
Is there any debate about the stupidity of p-values in economics. Why not CI?
This study examines the impact of this change on p-hacking and publication bias. The author employs a diff-in-diff design, as well as the battery of tests proposed by Elliott et al. (2022b). The author finds no statistically significant effect of this policy.
November 21, 2025 at 1:24 AM
Is there any debate about the stupidity of p-values in economics. Why not CI?
What scientists are you. I mean some are better than others.
Interested in the good science that is not corrupted by dark research funding money and 10% funding rates.
Interested in the good science that is not corrupted by dark research funding money and 10% funding rates.
Trust in science will increase when we stop all the money being used to fund anti-science political attacks and spread disinformation.
November 20, 2025 at 4:26 AM
What scientists are you. I mean some are better than others.
Interested in the good science that is not corrupted by dark research funding money and 10% funding rates.
Interested in the good science that is not corrupted by dark research funding money and 10% funding rates.