Z-curve
@replicationindex.com
MetaScience, MetaScientist, MetaPsycholog, UberScientist
Pinned
Z-curve
@replicationindex.com
· Nov 13
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...
@steamtraen.eu you may like this. A forest plot of the strongest nudging studies in Mertens 2022 meta-analysis.
September 6, 2026 at 5:00 AM
@steamtraen.eu you may like this. A forest plot of the strongest nudging studies in Mertens 2022 meta-analysis.
"Aiming to rejecting the nil hypothesis is foolish, aiming to accept it is insanity" (paraphrasing Savage).
September 2, 2026 at 5:31 PM
"Aiming to rejecting the nil hypothesis is foolish, aiming to accept it is insanity" (paraphrasing Savage).
Ancient history by now, but a little twist to the Bargh-Kahneman exchange. A meta-analysis of studies in 2012 shows no evidence for elderly priming and Doyen et al. were not the first to publish a replication failure.
replicationindex.com/2026/08/09/e...
replicationindex.com/2026/08/09/e...
Elderly Priming: Did It Ever Work? - Replicability-Index
The Short Version Bargh, Chen, and Burrows (1996) reported that priming students with words related to old age made them walk more slowly, with effect sizes above one standard deviation (d = 1.04 and ...
replicationindex.com
August 10, 2026 at 4:05 AM
Ancient history by now, but a little twist to the Bargh-Kahneman exchange. A meta-analysis of studies in 2012 shows no evidence for elderly priming and Doyen et al. were not the first to publish a replication failure.
replicationindex.com/2026/08/09/e...
replicationindex.com/2026/08/09/e...
The only non-significant result, psychology journals will publish. We found no evidence of publication bias. LOL
August 3, 2026 at 8:35 PM
The only non-significant result, psychology journals will publish. We found no evidence of publication bias. LOL
When meta-scientists wanted to study whether science works, they put psychology in the control group.
August 3, 2026 at 3:08 PM
When meta-scientists wanted to study whether science works, they put psychology in the control group.
The insanity of meta-analyses of pathological literatures.
Four hundred individually “successful” studies should not culminate in uncertainty about whether the foundational effect exists at all.
Four hundred individually “successful” studies should not culminate in uncertainty about whether the foundational effect exists at all.
August 2, 2026 at 2:20 PM
The insanity of meta-analyses of pathological literatures.
Four hundred individually “successful” studies should not culminate in uncertainty about whether the foundational effect exists at all.
Four hundred individually “successful” studies should not culminate in uncertainty about whether the foundational effect exists at all.
Somebody needs to do the dirty work to keep a place clean and functioning. Call me #TheCustodian of psychological science. :)
August 2, 2026 at 1:43 PM
Somebody needs to do the dirty work to keep a place clean and functioning. Call me #TheCustodian of psychological science. :)
Reposted by Z-curve
Nobody ever called psychology #TemuScience 😷
July 28, 2026 at 5:30 PM
Nobody ever called psychology #TemuScience 😷
Reposted by Z-curve
How powerful are bias tests? Turns out not very much, even with k = 300 studies. A better way to deal with publication bias is to estimate it with confidence intervals and focus on the upper bound (not the lower bound, lb > 0, there is bias, p < .05).
arxiv.org/abs/2607.19626
arxiv.org/abs/2607.19626
Beyond Publication-Bias Detection: Estimating Bias under Uncertainty in Heterogeneous Literatures
Meta-analysts routinely test for publication bias, but a nonsignificant test is inconclusive because it may be a Type 2 error. In a large factorial simulation, I show that publication-bias tests have ...
arxiv.org
July 23, 2026 at 1:32 AM
How powerful are bias tests? Turns out not very much, even with k = 300 studies. A better way to deal with publication bias is to estimate it with confidence intervals and focus on the upper bound (not the lower bound, lb > 0, there is bias, p < .05).
arxiv.org/abs/2607.19626
arxiv.org/abs/2607.19626
Reposted by Z-curve
Most corrupt administration in American history!
July 15, 2026 at 9:13 AM
Most corrupt administration in American history!
"Hi Lindsay, damn it is hot here. I hope we get used to it in eternity."
Curious to hear Mitch McConnell's comments on the passing of Lindsey Graham.
July 12, 2026 at 4:33 PM
"Hi Lindsay, damn it is hot here. I hope we get used to it in eternity."
#RMA #Metafor #MetaAnalysis
by tradition, random effects models in meta-analysis assume a normal distribution of population effect sizes. This is a problem. The assumption is neither plausible nor necessary.
Modern mixture models solve the problem.
replicationindex.com/2026/07/12/w...
by tradition, random effects models in meta-analysis assume a normal distribution of population effect sizes. This is a problem. The assumption is neither plausible nor necessary.
Modern mixture models solve the problem.
replicationindex.com/2026/07/12/w...
Why Most Meta-Analyses (in Psychology) are False: Mismodeling Heterogeneity - Replicability-Index
This blog post follows up on an introduction to meta-analyses with heterogeneous data. Modeling Heterogeneity in Meta-Analyses - Replicability-Index We can distinguish two types of meta-analysis. Meta...
replicationindex.com
July 12, 2026 at 4:23 PM
#RMA #Metafor #MetaAnalysis
by tradition, random effects models in meta-analysis assume a normal distribution of population effect sizes. This is a problem. The assumption is neither plausible nor necessary.
Modern mixture models solve the problem.
replicationindex.com/2026/07/12/w...
by tradition, random effects models in meta-analysis assume a normal distribution of population effect sizes. This is a problem. The assumption is neither plausible nor necessary.
Modern mixture models solve the problem.
replicationindex.com/2026/07/12/w...
Reposted by Z-curve
Xitter's community notes are working overtime calling out people trying to claim Mamdani's attempts to conserve power is socialist. This one might be my favorite.
July 2, 2026 at 5:29 PM
Xitter's community notes are working overtime calling out people trying to claim Mamdani's attempts to conserve power is socialist. This one might be my favorite.
Reposted by Z-curve
I'm working on a new Metacheck module: Datacheck. Repocheck already lists all files on Github, Zenodo, OSF, Researchbox. Datacheck will download them and.... which automated checks would you like for datafiles? Can be general (e.g., flag outliers), or file specific (e.g., excel files). Let me know 👇
July 2, 2026 at 3:46 PM
I'm working on a new Metacheck module: Datacheck. Repocheck already lists all files on Github, Zenodo, OSF, Researchbox. Datacheck will download them and.... which automated checks would you like for datafiles? Can be general (e.g., flag outliers), or file specific (e.g., excel files). Let me know 👇
Testing the assumptions of step-function selection models with z-curve.
replicationindex.com/2026/06/26/t...
replicationindex.com/2026/06/26/t...
To Model or Not to Model Nonsignificant Results in Meta-Analyses? Testing the Step-Function Model’s Assumption - Replicability-Index
To make sense of empirical data, researchers need statistical models, and the choice of model can influence conclusions. It is therefore important to be aware of the assumptions a model makes and, ide...
replicationindex.com
June 27, 2026 at 3:04 AM
Testing the assumptions of step-function selection models with z-curve.
replicationindex.com/2026/06/26/t...
replicationindex.com/2026/06/26/t...
Pathological Meta-Science: All pain, no gain.
June 25, 2026 at 4:48 PM
Pathological Meta-Science: All pain, no gain.
Reposted by Z-curve
New preprint: There is only one correct analysis. osf.io/preprints/ps...
with @sajedehra.bsky.social and @mntunc.bsky.social
We take a critical look at recent proposals for multiverse or many analyst procedures, and strongly argue that epistemic uncertainty should be reduced, not “embraced”. >
with @sajedehra.bsky.social and @mntunc.bsky.social
We take a critical look at recent proposals for multiverse or many analyst procedures, and strongly argue that epistemic uncertainty should be reduced, not “embraced”. >
OSF
osf.io
June 21, 2026 at 2:11 PM
New preprint: There is only one correct analysis. osf.io/preprints/ps...
with @sajedehra.bsky.social and @mntunc.bsky.social
We take a critical look at recent proposals for multiverse or many analyst procedures, and strongly argue that epistemic uncertainty should be reduced, not “embraced”. >
with @sajedehra.bsky.social and @mntunc.bsky.social
We take a critical look at recent proposals for multiverse or many analyst procedures, and strongly argue that epistemic uncertainty should be reduced, not “embraced”. >
Statistical Power is nearly 100 years old, but the concept is still misunderstood, especially in applications that examine how much power researchers really had to get their significant results.
open.lnu.se/index.php/me...
open.lnu.se/index.php/me...
LnuOpen
| Meta-Psychology
open.lnu.se
June 22, 2026 at 4:32 PM
Statistical Power is nearly 100 years old, but the concept is still misunderstood, especially in applications that examine how much power researchers really had to get their significant results.
open.lnu.se/index.php/me...
open.lnu.se/index.php/me...
"You Cannot Step Into the Same River Twice", but you can "step into it" again and again.
A snarky post on McShane's rhetorical simulation studies.
replicationindex.com/2026/06/13/s...
A snarky post on McShane's rhetorical simulation studies.
replicationindex.com/2026/06/13/s...
Simulations as Rhetorical Devices - Replicability-Index
The past decade has not been kind to experimental social psychology. Study after study failed to replicate and entire literatures have turned out to be built on nothing (a.k.a. statistical noise minin...
replicationindex.com
June 14, 2026 at 4:10 AM
"You Cannot Step Into the Same River Twice", but you can "step into it" again and again.
A snarky post on McShane's rhetorical simulation studies.
replicationindex.com/2026/06/13/s...
A snarky post on McShane's rhetorical simulation studies.
replicationindex.com/2026/06/13/s...
Reposted by Z-curve
A Cochrane system for checking whether any of its thousands of published reviews include retracted studies has already turned up dozens of reviews that do and will now get closer scrutiny to ensure their results and recommendations hold up.
New system for flagging retracted papers finds scores of them in Cochrane reviews
Cochrane has implemented a new system for checking whether any of its thousands of published reviews include retracted studies in their analyses, the organization announced today. The effort alread…
retractionwatch.com
June 10, 2026 at 6:41 PM
A Cochrane system for checking whether any of its thousands of published reviews include retracted studies has already turned up dozens of reviews that do and will now get closer scrutiny to ensure their results and recommendations hold up.
Maybe AI is not really smart, intelligent, etc. what ever that means. Maybe we should give it an IQ test (LOL).
However, it is much more rational than humans. Human intelligence is often wasted and compromised by self-deception willful ignorance, and cognitive biases that won KT a Nobel.
However, it is much more rational than humans. Human intelligence is often wasted and compromised by self-deception willful ignorance, and cognitive biases that won KT a Nobel.
June 11, 2026 at 5:12 PM
Maybe AI is not really smart, intelligent, etc. what ever that means. Maybe we should give it an IQ test (LOL).
However, it is much more rational than humans. Human intelligence is often wasted and compromised by self-deception willful ignorance, and cognitive biases that won KT a Nobel.
However, it is much more rational than humans. Human intelligence is often wasted and compromised by self-deception willful ignorance, and cognitive biases that won KT a Nobel.
Reposted by Z-curve
My PhD Sajedeh Rasti has published a World View piece in Nature today: "Don’t compete, collaborate: why collective funding applications are the future" www.nature.com/articles/d41... She discusses how she successfully brought together a team of meta-scientists to collaboratively apply for funding.
Don’t compete, collaborate: why collective funding applications are the future
Scientists with disparate expertise writing grants together can identify knowledge gaps and drive progress — but systems must change to incentivize them.
www.nature.com
June 10, 2026 at 11:46 AM
My PhD Sajedeh Rasti has published a World View piece in Nature today: "Don’t compete, collaborate: why collective funding applications are the future" www.nature.com/articles/d41... She discusses how she successfully brought together a team of meta-scientists to collaboratively apply for funding.
Every math teacher when students say they will never need it in real life. Are you human?
June 10, 2026 at 2:01 PM
Every math teacher when students say they will never need it in real life. Are you human?