František Bartoš
@fbartos.bsky.social
PhD Candidate | Psychological Methods | UvA Amsterdam | interested in statistics, meta-analysis, and publication bias | once flipped a coin too many times
Pinned
František Bartoš
@fbartos.bsky.social
· Sep 17
We released two preprints describing the JASP Meta-Analytic functionality in detail.
Meta-Analysis with JASP, Part I: Classical Approaches (arxiv.org/abs/2509.09845)
Meta-Analysis with JASP, Part II: Bayesian Approaches (arxiv.org/abs/2509.09850)
Meta-Analysis with JASP, Part I: Classical Approaches (arxiv.org/abs/2509.09845)
Meta-Analysis with JASP, Part II: Bayesian Approaches (arxiv.org/abs/2509.09850)
Reposted by František Bartoš
Everything is ready for the Perspectives on Scientific Error conference that starts tomorrow in Leiden! I look forward to hanging out with the mix of metascientists, philosophers of science, and statisticians! So many old friends will be there (and hopefully some new ones)! #PSE8
February 10, 2026 at 5:10 PM
Everything is ready for the Perspectives on Scientific Error conference that starts tomorrow in Leiden! I look forward to hanging out with the mix of metascientists, philosophers of science, and statisticians! So many old friends will be there (and hopefully some new ones)! #PSE8
Come to Amsterdam or join online for the full week of JASP workshops (24th-28th of August)! If you can't do the full week or you are only interested in meta-analysis, I will be giving the Meta-Analysis workshop on 25th of August.
jasp-stats.org/2026/02/05/h...
jasp-stats.org/2026/02/05/h...
February 6, 2026 at 9:23 AM
Come to Amsterdam or join online for the full week of JASP workshops (24th-28th of August)! If you can't do the full week or you are only interested in meta-analysis, I will be giving the Meta-Analysis workshop on 25th of August.
jasp-stats.org/2026/02/05/h...
jasp-stats.org/2026/02/05/h...
Reposted by František Bartoš
Does it make sense to preregister simulation studies?
This question has sparked a lot of debate.
▶️We* work through the why, when, and how
▶️We discuss different phases of methodological research to clarify where preregistration might (or might not) add value
📝 Preprint: doi.org/10.31234/osf...
This question has sparked a lot of debate.
▶️We* work through the why, when, and how
▶️We discuss different phases of methodological research to clarify where preregistration might (or might not) add value
📝 Preprint: doi.org/10.31234/osf...
February 4, 2026 at 10:40 AM
Does it make sense to preregister simulation studies?
This question has sparked a lot of debate.
▶️We* work through the why, when, and how
▶️We discuss different phases of methodological research to clarify where preregistration might (or might not) add value
📝 Preprint: doi.org/10.31234/osf...
This question has sparked a lot of debate.
▶️We* work through the why, when, and how
▶️We discuss different phases of methodological research to clarify where preregistration might (or might not) add value
📝 Preprint: doi.org/10.31234/osf...
We just posted a preprint with a comprehensive meta-meta-analysis of the effects of AI/LLMs on learning.
TLDR:
- 1,840 effect sizes
- extreme between-study heterogeneity
- extreme publication bias
- small average effects (three times lower than usually reported)
(osf.io/preprints/ps...)
TLDR:
- 1,840 effect sizes
- extreme between-study heterogeneity
- extreme publication bias
- small average effects (three times lower than usually reported)
(osf.io/preprints/ps...)
January 28, 2026 at 8:41 PM
We just posted a preprint with a comprehensive meta-meta-analysis of the effects of AI/LLMs on learning.
TLDR:
- 1,840 effect sizes
- extreme between-study heterogeneity
- extreme publication bias
- small average effects (three times lower than usually reported)
(osf.io/preprints/ps...)
TLDR:
- 1,840 effect sizes
- extreme between-study heterogeneity
- extreme publication bias
- small average effects (three times lower than usually reported)
(osf.io/preprints/ps...)
Reposted by František Bartoš
Edgeworth proposed the alpha=.005 criterion 134 years prior to Benjamin et al. (2019). :-)
www.bayesianspectacles.org/redefine-sta...
www.bayesianspectacles.org/redefine-sta...
Redefine Statistical Significance Part XXI: Edgeworth Proposed the .005 Criterion Back in 1885
The statistical significance test was not invented by Ronald Fisher. The key idea was already laid out by Francis Ysidro Edgeworth (1845-1926), whose 1885 article “Methods of statistics”…
www.bayesianspectacles.org
January 14, 2026 at 11:41 AM
Edgeworth proposed the alpha=.005 criterion 134 years prior to Benjamin et al. (2019). :-)
www.bayesianspectacles.org/redefine-sta...
www.bayesianspectacles.org/redefine-sta...
Reposted by František Bartoš
The world's earliest recorded outlier? Let me know if you have an even older example!
www.jasp-services.com/jasp-for-qua...
www.jasp-services.com/jasp-for-qua...
JASP for Quality Control, Example 6: The World's Earliest Recorded Outlier? - JASP Services BV
Information hidden in raw data can be revealed most easily by means of statistical visualization techniques (“always plot your data”). To demonstrate I will now analyze the duration of reign (in years...
www.jasp-services.com
December 24, 2025 at 1:09 PM
The world's earliest recorded outlier? Let me know if you have an even older example!
www.jasp-services.com/jasp-for-qua...
www.jasp-services.com/jasp-for-qua...
"we did not find any evidence for publication bias (p=0.077)"
December 23, 2025 at 7:49 PM
"we did not find any evidence for publication bias (p=0.077)"
The Robust Bayesian Meta-Analysis package got updated with additional vignettes explaining how to perform Bayesian model-averaged publication bias-adjusted
- multilevel meta-analysis (cran.r-project.org/web/packages...)
- multilevel meta-regression (cran.r-project.org/web/packages...)
- multilevel meta-analysis (cran.r-project.org/web/packages...)
- multilevel meta-regression (cran.r-project.org/web/packages...)
Multilevel Robust Bayesian Meta-Analysis
cran.r-project.org
December 23, 2025 at 10:11 AM
The Robust Bayesian Meta-Analysis package got updated with additional vignettes explaining how to perform Bayesian model-averaged publication bias-adjusted
- multilevel meta-analysis (cran.r-project.org/web/packages...)
- multilevel meta-regression (cran.r-project.org/web/packages...)
- multilevel meta-analysis (cran.r-project.org/web/packages...)
- multilevel meta-regression (cran.r-project.org/web/packages...)
Reposted by František Bartoš
I recently bought 20 bags of potato that, according to the Albert Heijn supermarket, should each contain 1 kg. This turns out to be *false*.
www.jasp-services.com/at-the-alber...
www.jasp-services.com/at-the-alber...
At the Albert Heijn, You Get About 2% More Potatoes Than What it Says on the Label - JASP Services BV
A week ago I started a small quality control project where I measured twenty “1 kg” Albert Heijn (AH) potato bags in order to assess whether or not AH is systematically underfilling them, as some soci...
www.jasp-services.com
December 17, 2025 at 9:51 PM
I recently bought 20 bags of potato that, according to the Albert Heijn supermarket, should each contain 1 kg. This turns out to be *false*.
www.jasp-services.com/at-the-alber...
www.jasp-services.com/at-the-alber...
Reposted by František Bartoš
The suspense is building: do the measurements of 20 units indicate that the Albert Heijn underfills its 1 kg bags of potatoes? An interim post on the importance of articulating your predictions *before* seeing the results. :-)
www.jasp-services.com/do-the-1kg-a...
www.jasp-services.com/do-the-1kg-a...
Do the 1kg Albert Heijn Potato Bags Really Contain 1kg of Potatoes? - JASP Services BV
A few days ago I announced a small quality control project where I would measure 20 bags of “1 kg” Albert Heijn (AH) potato bags to assess whether or not AH is systematically underfilling them, as som...
www.jasp-services.com
December 12, 2025 at 11:43 AM
The suspense is building: do the measurements of 20 units indicate that the Albert Heijn underfills its 1 kg bags of potatoes? An interim post on the importance of articulating your predictions *before* seeing the results. :-)
www.jasp-services.com/do-the-1kg-a...
www.jasp-services.com/do-the-1kg-a...
Reposted by František Bartoš
This week's blog post features "raincloud plots", a relatively recent development in data visualization.
Will the raincloud plot gradually replace the box plot? It just might!
Check out the raincloud plot for the planets in our solar system at
www.jasp-services.com/jasp-for-qua...
Will the raincloud plot gradually replace the box plot? It just might!
Check out the raincloud plot for the planets in our solar system at
www.jasp-services.com/jasp-for-qua...
JASP for Quality Control, Example 4: The Raincloud Plot - JASP Services BV
In our last post we discussed the boxplot of the distances to the sun for each of the eight planets in our solar system, as measured in astronomical units (AU; AU=1 is the average distance from the ea...
www.jasp-services.com
December 3, 2025 at 9:39 AM
This week's blog post features "raincloud plots", a relatively recent development in data visualization.
Will the raincloud plot gradually replace the box plot? It just might!
Check out the raincloud plot for the planets in our solar system at
www.jasp-services.com/jasp-for-qua...
Will the raincloud plot gradually replace the box plot? It just might!
Check out the raincloud plot for the planets in our solar system at
www.jasp-services.com/jasp-for-qua...
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...)
Reposted by František Bartoš
Feb 16-17: JASP Hackathon in Amsterdam!
Now open for applications
Post with details on the JASP website:
jasp-stats.org/2025/11/21/a...
Now open for applications
Post with details on the JASP website:
jasp-stats.org/2025/11/21/a...
Apply for the eScience JASP Hackathon and Build Your Own Module, in Amsterdam - JASP - Free and User-Friendly Statistical Software
tldr; On 16-17 February 2026 the Netherlands eScience Center is hosting a two-day JASP hackathon in Amsterdam. The purpose of the hackathon is to guide participants into developing their very own JASP...
jasp-stats.org
November 26, 2025 at 10:50 AM
Feb 16-17: JASP Hackathon in Amsterdam!
Now open for applications
Post with details on the JASP website:
jasp-stats.org/2025/11/21/a...
Now open for applications
Post with details on the JASP website:
jasp-stats.org/2025/11/21/a...
Reposted by František Bartoš
New blogpost on our JRR website!
Check out our new blogpost (link below): we highlight a study for re-analysis on whether CEOs are shaped by their daughters. This could be a potential candidate for a robustness report.
www.journalofrobustnessreports.org/are-ceos-sha...
Check out our new blogpost (link below): we highlight a study for re-analysis on whether CEOs are shaped by their daughters. This could be a potential candidate for a robustness report.
www.journalofrobustnessreports.org/are-ceos-sha...
Are CEOs Shaped by Their Daughters? - Journal of Robustness Reports
In this blogpost I wish to highlight the following article as a candidate for a set of Robustness Reports: Cronqvist, H., & Yu, F. (2017). Shaped by their daughters: Executives, female socialization, ...
www.journalofrobustnessreports.org
November 11, 2025 at 10:40 PM
New blogpost on our JRR website!
Check out our new blogpost (link below): we highlight a study for re-analysis on whether CEOs are shaped by their daughters. This could be a potential candidate for a robustness report.
www.journalofrobustnessreports.org/are-ceos-sha...
Check out our new blogpost (link below): we highlight a study for re-analysis on whether CEOs are shaped by their daughters. This could be a potential candidate for a robustness report.
www.journalofrobustnessreports.org/are-ceos-sha...
Reposted by František Bartoš
"Always plot your data" -- an example of using descriptives *before* measuring capability of an instrument. We intend to have regular posts demonstrating how JASP can be useful for quality control and lean six sigma.
www.jasp-services.com/jasp-for-qua...
www.jasp-services.com/jasp-for-qua...
JASP for Quality Control, Example 1: Descriptives (aka "Always Plot Your Data") - JASP Services BV
To showcase how JASP can be used for statistical quality control we initiate a series of blog posts in which JASP is used to execute key statistical tasks. In this series’ inaugural post, I will go ov...
www.jasp-services.com
October 28, 2025 at 12:08 PM
"Always plot your data" -- an example of using descriptives *before* measuring capability of an instrument. We intend to have regular posts demonstrating how JASP can be useful for quality control and lean six sigma.
www.jasp-services.com/jasp-for-qua...
www.jasp-services.com/jasp-for-qua...
Reposted by František Bartoš
We just started a website highlighting articles that would make good candidates for a Robustness Report.
🌐 Check out the website: www.journalofrobustnessreports.org
📄 Read our first blog post: www.journalofrobustnessreports.org/inaugural-po...
🌐 Check out the website: www.journalofrobustnessreports.org
📄 Read our first blog post: www.journalofrobustnessreports.org/inaugural-po...
Journal of Robustness Reports
The Journal of Robustness Reports The Journal of Robustness Reports (JRR) is a diamond open-access journal that focuses on the reanalysis of high-impact empirical findings. JRR contains collections of...
www.journalofrobustnessreports.org
October 28, 2025 at 10:55 AM
We just started a website highlighting articles that would make good candidates for a Robustness Report.
🌐 Check out the website: www.journalofrobustnessreports.org
📄 Read our first blog post: www.journalofrobustnessreports.org/inaugural-po...
🌐 Check out the website: www.journalofrobustnessreports.org
📄 Read our first blog post: www.journalofrobustnessreports.org/inaugural-po...
Reposted by František Bartoš
We built the openESM database:
▶️60 openly available experience sampling datasets (16K+ participants, 740K+ obs.) in one place
▶️Harmonized (meta-)data, fully open-source software
▶️Filter & search all data, simply download via R/Python
Find out more:
🌐 openesmdata.org
📝 doi.org/10.31234/osf...
▶️60 openly available experience sampling datasets (16K+ participants, 740K+ obs.) in one place
▶️Harmonized (meta-)data, fully open-source software
▶️Filter & search all data, simply download via R/Python
Find out more:
🌐 openesmdata.org
📝 doi.org/10.31234/osf...
October 22, 2025 at 7:34 PM
We built the openESM database:
▶️60 openly available experience sampling datasets (16K+ participants, 740K+ obs.) in one place
▶️Harmonized (meta-)data, fully open-source software
▶️Filter & search all data, simply download via R/Python
Find out more:
🌐 openesmdata.org
📝 doi.org/10.31234/osf...
▶️60 openly available experience sampling datasets (16K+ participants, 740K+ obs.) in one place
▶️Harmonized (meta-)data, fully open-source software
▶️Filter & search all data, simply download via R/Python
Find out more:
🌐 openesmdata.org
📝 doi.org/10.31234/osf...
Simulation studies have a conflict of interest problem. The same team:
- develops a new method
- designs a simulation study to evaluate it
However, the new method has to show good performance to get published.
We propose living synthetic benchmarks to address the issue (doi.org/10.48550/arX...).
- develops a new method
- designs a simulation study to evaluate it
However, the new method has to show good performance to get published.
We propose living synthetic benchmarks to address the issue (doi.org/10.48550/arX...).
October 23, 2025 at 4:02 PM
Simulation studies have a conflict of interest problem. The same team:
- develops a new method
- designs a simulation study to evaluate it
However, the new method has to show good performance to get published.
We propose living synthetic benchmarks to address the issue (doi.org/10.48550/arX...).
- develops a new method
- designs a simulation study to evaluate it
However, the new method has to show good performance to get published.
We propose living synthetic benchmarks to address the issue (doi.org/10.48550/arX...).
Reposted by František Bartoš
New blog post! Why companies win by investing in open-source software. With zebra-painted cows, of course.
www.jasp-services.com/why-companie...
www.jasp-services.com/why-companie...
Why Companies Win by Investing in Open-Source Software - JASP Services BV
In 2025, the IgNobel prize in Biology went to research on “whether cows painted with zebra-like striping can avoid being bitten by flies“. Suppose a fictitious company, ZebraCows, wishes to exploit th...
www.jasp-services.com
September 30, 2025 at 12:29 PM
New blog post! Why companies win by investing in open-source software. With zebra-painted cows, of course.
www.jasp-services.com/why-companie...
www.jasp-services.com/why-companie...
Reposted by František Bartoš
We are pleased to have
@fbartos.bsky.social
join us today, Tuesday, September 30th, 11am (EST) to talk about Bayesian Hypothesis testing! This is followed by a workshop on using JASP for statistics around 12:10pm. The zoom is open to public with details in the flyer!
@PsychPrinceton
@fbartos.bsky.social
join us today, Tuesday, September 30th, 11am (EST) to talk about Bayesian Hypothesis testing! This is followed by a workshop on using JASP for statistics around 12:10pm. The zoom is open to public with details in the flyer!
@PsychPrinceton
September 30, 2025 at 11:43 AM
We are pleased to have
@fbartos.bsky.social
join us today, Tuesday, September 30th, 11am (EST) to talk about Bayesian Hypothesis testing! This is followed by a workshop on using JASP for statistics around 12:10pm. The zoom is open to public with details in the flyer!
@PsychPrinceton
@fbartos.bsky.social
join us today, Tuesday, September 30th, 11am (EST) to talk about Bayesian Hypothesis testing! This is followed by a workshop on using JASP for statistics around 12:10pm. The zoom is open to public with details in the flyer!
@PsychPrinceton
Reposted by František Bartoš
Simonsohn has now posted a blog response to our recent paper about the poor statistical properties of the P curve. @clintin.bsky.social and I are finishing up a less-technical paper that will serve as a response. But I wanted to address a meta-issue *around* this that may clarify some things. 1/x
Would p-curve work if you dropped a piano on it?
datacolada.org/129
datacolada.org/129
September 25, 2025 at 10:07 AM
Simonsohn has now posted a blog response to our recent paper about the poor statistical properties of the P curve. @clintin.bsky.social and I are finishing up a less-technical paper that will serve as a response. But I wanted to address a meta-issue *around* this that may clarify some things. 1/x
Reposted by František Bartoš
Sage created a 44-second promo video for our book "Discovering Statistics Using JASP". Blog post: jasp-stats.org/2025/09/24/d...
The video itself: www.youtube.com/watch?v=MP0N...
The video itself: www.youtube.com/watch?v=MP0N...
"Discovering Statistics Using JASP": The Promo Video - JASP - Free and User-Friendly Statistical Software
The shiny new textbook “Discovering Statistics Using JASP” now has a 44-second promo video on YouTube, courtesy of Sage. What I like about the video is that it shows some of the pages, so you get an o...
jasp-stats.org
September 24, 2025 at 7:08 AM
Sage created a 44-second promo video for our book "Discovering Statistics Using JASP". Blog post: jasp-stats.org/2025/09/24/d...
The video itself: www.youtube.com/watch?v=MP0N...
The video itself: www.youtube.com/watch?v=MP0N...
Can anyone point me to the simulation studies showing that p-curve performs well under realistic conditions? And any done by someone else than pcurve authors? As far as I know, p-curve fails horrendously as long as any heterogeneity is involved...
doi.org/10.1177/1745...
doi.org/10.1002/jrsm...
doi.org/10.1177/1745...
doi.org/10.1002/jrsm...
September 24, 2025 at 6:51 AM
Can anyone point me to the simulation studies showing that p-curve performs well under realistic conditions? And any done by someone else than pcurve authors? As far as I know, p-curve fails horrendously as long as any heterogeneity is involved...
doi.org/10.1177/1745...
doi.org/10.1002/jrsm...
doi.org/10.1177/1745...
doi.org/10.1002/jrsm...
We released two preprints describing the JASP Meta-Analytic functionality in detail.
Meta-Analysis with JASP, Part I: Classical Approaches (arxiv.org/abs/2509.09845)
Meta-Analysis with JASP, Part II: Bayesian Approaches (arxiv.org/abs/2509.09850)
Meta-Analysis with JASP, Part I: Classical Approaches (arxiv.org/abs/2509.09845)
Meta-Analysis with JASP, Part II: Bayesian Approaches (arxiv.org/abs/2509.09850)
September 17, 2025 at 9:40 AM
We released two preprints describing the JASP Meta-Analytic functionality in detail.
Meta-Analysis with JASP, Part I: Classical Approaches (arxiv.org/abs/2509.09845)
Meta-Analysis with JASP, Part II: Bayesian Approaches (arxiv.org/abs/2509.09850)
Meta-Analysis with JASP, Part I: Classical Approaches (arxiv.org/abs/2509.09845)
Meta-Analysis with JASP, Part II: Bayesian Approaches (arxiv.org/abs/2509.09850)
Z-curve plot is a new visual model fit diagnostic for #metaanalysis with an emphasis on #publicationbias. In contrast to funnel plots, z-curve plots
- visualize the distribution of z-statistics (where bias usually occurs)
- compare the fit of multiple models simultaneously
- visualize the distribution of z-statistics (where bias usually occurs)
- compare the fit of multiple models simultaneously
September 10, 2025 at 9:42 AM
Z-curve plot is a new visual model fit diagnostic for #metaanalysis with an emphasis on #publicationbias. In contrast to funnel plots, z-curve plots
- visualize the distribution of z-statistics (where bias usually occurs)
- compare the fit of multiple models simultaneously
- visualize the distribution of z-statistics (where bias usually occurs)
- compare the fit of multiple models simultaneously