Lenni

Screenshot of the first page of the article, including title "Emphasising herd immunity in vaccine advocacy: a systematic review and meta-analysis", authors and abstract.

Emphasizing herd immunity might be a helpful strategy to improve vaccine uptake 💉 In this meta-analysis, authors found small positive, but heterogenous effects. Interestingly, effects are twice as large for experiential methods, such as VR or simulations!

Read the full paper here: doi.org/qc4j

[130] ResearchBox: Even Easier to Use and More Transparently Permanent than Before - Data Colada Over the past 10 years or so, posting data, code, and materials for published papers has gone from eccentric to mundane. There are a few platforms that enable sharing research files, including Researc...

[130] Researchbox: Even easier to use than before. More transparently permanent.
datacolada.org/130

Tomorrow marks the start of 🌍 World AMR Awareness Week 2025! We’ll be sharing insights from our AMR research as psychologists at @univie.ac.at @ipb.bsky.social @unierfurt.bsky.social and BNITM. Like/share this post for updates throughout the week! #AMR #WorldAMRAwarenessWeek #WAAW2025

Stop being a lame-o and replace dplyr with the more slappin genzplyr.

Ouch

We're hiring! @univie.ac.at is seeking a TT Assistant Professor in the Psychology of Digitalization. If your work is about automation, AI, or immersive technology (e.g., VR) in the context of work and organizations (broadly defined), we’d love to hear from you. 👇

Title: A Justification for 80% Power Abstract: Cohen’s heuristic reason for choosing 80% power (balancing Type I and TypeII errors) conveniently arrives at approximately the same number as an approachwhere one maximizes the marginal gain in power per standard error reduction. Ihave yet to see someone point this out, and this is interesting because it providesa non-arbitrary justification for 80% power.

a derivation of the result

I think this is kind of neat and I don't think anyone else has noticed it (I've looked and I can't find anyone who has) osf.io/preprints/so...

Maybe I should back off "justification" language, but it's at least a remarkable coincidence. I still think someone else *must* have noticed it...

AI discovers learning algorithm that outperforms those designed by humans An artificial-intelligence algorithm that discovers its own way to learn achieves state-of-the-art performance, including on some tasks it had never encountered before.

An AI algorithm that discovers its own way to learn achieves state-of-the-art performance, including on some tasks it had never encountered before

go.nature.com/3L4AmKL

The multi-level social dilemmas of intergroup interactions - Nature Reviews Psychology Nature Reviews Psychology - The multi-level social dilemmas of intergroup interactions

My PhD student @qinyuxiao.bsky.social has written a wonderful tribute to Gary Bornstein’s influential paper on team games (doi.org/10.1207/S153...) — a paper that remains as relevant today as it was over 20 years ago. You can read Qinyu’s short piece here: doi.org/10.1038/s441...

Indeed, your article was by far the easiest to code 🙂. That really reflects the clarity and transparency of your reporting—much appreciated!

Thank you for all the help and guidance! I couldn't ask for a better mentor 🫶

No, Qinyu, you rock 🥹

The article is open access 🔓, preregistered 📑, and fully transparent: we share all data, effect size computations, screenshots of extracted effects, and full analysis code. 🧑‍💻📂 Just see the post above.

That's all! End of thread! Thanks for your attention <3

Emphasising herd immunity in vaccine advocacy: a systematic review and meta-analysis Emphasising herd immunity in vaccine communication may affect vaccine uptake by eliciting prosocial or selfish motivations. While experimental evidence has accumulated, quantitative syntheses are l...

📖 doi.org/10.1080/1743...

📂 osf.io/zm9at/

📝 Preregistration: PROSPERO CRD42024540536

Personal note: this is the most work I’ve ever put into a project (yet). I learned so much, and I’m grateful to see it published. With vaccine hesitancy rising, it’s important to remember that every (non-)vaccination also has a social impact

Takeaway 💡
Communicating herd immunity has a small but positive effect on vaccination motivation. However, the effect is larger when people can experience it (VR, simulations) instead of just reading text. 🚀

As such, future messages must be clear, engaging & immersive 🕶️💉

We also ran some fancy machine learning 🧠, multiple tests for publication bias (spoiler: none found ✅), assessed Risk of Bias (all good), and packed in plenty of other cool stuff (including a HUGE table 📊).
For all the details—you’ll have to check out the paper 😉

Among the most relevant moderators, we identify the medium of communication. When people can actually experience herd immunity (e.g., VR, simulations), the effect on vaccination motivation more than doubles (g = 0.29) 🚀

📊 Herd immunity messages do boost vaccination motivation! We find a small but positive summary effect: g = 0.12 (95% CI: 0.08–0.17) 📈 But averages only tell part of the story—what’s even more interesting is when and how these messages work. That’s what we tested next.

To find out, we ran the first systematic review & meta-analysis on herd immunity communication 🧪
🔎 10+ years of experimental work
📂 a whole lot of records screened
📊 43 studies (67 effects), >100k participants
⚙️ Three-level model + Publication Bias Tests + MetaForest

So… what did we discover? 👀

💉 Communicating HI could have different effects:
👉 It could motivate prosocial vaccination (“I’ll vaccinate to protect others”)
👉 But it could also motivate selfish-rational non-vaccination (“I’m safe if others vaccinate”)

Which is it? Does communicating HI help vaccination motivation? 🤔

Vaccines are a huge achievement ❤️💉. By getting vaccinated, you not only protect yourself but also protect others indirectly, as it is more difficult for the pathogen to spread. This is a simplified explanation of herd immunity (HI).

Yet, communicating HI could lead to several outcomes💉🤔

Emphasising herd immunity in vaccine advocacy: a systematic review and meta-analysis Emphasising herd immunity in vaccine communication may affect vaccine uptake by eliciting prosocial or selfish motivations. While experimental evidence has accumulated, quantitative syntheses are l...

📢 New SysRev + Meta-Analysis out in Health Psychology Review!
Together with the amazing Martin Voracek, @corneliabetsch.bsky.social & @robertboehm.bsky.social

Do messages about herd immunity increase or decrease vaccination motivation? 🤔
Read more to find out! 🧵
OA: doi.org/10.1080/1743...

Delegation to artificial intelligence can increase dishonest behaviour - Nature People cheat more when they delegate&nbsp;tasks to artificial intelligence, and large language models are more likely than humans to comply with unethical instructions—a risk that can be minimized by ...

🚨 Beyond excited that our new paper is out today in @natureportfolio.nature.com

We find that people are more likely to cheat when they delegate to AI than when acting themselves.

www.nature.com/articles/s41...

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

A shout out for @nrennie.bsky.social fab book on data viz! nrennie.rbind.io/art-of-viz/

"Understanding different types of review articles: A primer for early career researchers."

By Ghosh & Choudhury (2025)

Open Access: dx.doi.org/10.4103/indi...

#AcademicSky #PhDSky #Methodology

Happy to announce ✨quarto-revealjs-editable✨

This fully supersedes the imagemover extension, as I back then didn't realize the potential. You can now also move, resize, change font size and alignment for text in your slides

github.com/EmilHvitfeld...
#quarto #slidecrafting

Cover page for the manuscript: Morey, R. D., & Davis-Stober, C. P. (2025). On the poor statistical properties of the P-curve meta-analytic procedure. Journal of the American Statistical Association, 1–19. https://doi.org/10.1080/01621459.2025.2544397

Abstract for the paper: The P-curve (Simonsohn, Nelson, & Simmons, 2014; Simonsohn, Simmons, & Nelson, 2015) is a widely-used suite of meta-analytic tests advertised for detecting problems in sets of studies. They are based on nonparametric combinations of p values (e.g., Marden, 1985) across significant (p < .05) studies and are variously claimed to detect “evidential value”, “lack of evidential value”, and “left skew” in p values. We show that these tests do not have the properties ascribed to them. Moreover, they fail basic desiderata for tests, including admissibility and monotonicity. In light of these serious problems, we recommend against the use of the P-curve tests.

Paper drop, for anyone interested in #metascience, #statistics, or #metaanalysis! @clintin.bsky.social and I show in a new paper in JASA that the P-curve, a popular forensic meta-analysis method, has deeply undesirable statistical properties. www.tandfonline.com/doi/full/10.... 1/?

Easily download files from the Open Science Framework with Papercheck Researchers increasingly use the Open Science Framework (OSF) to share files, such as data and code underlying scientific publications, or ...

New blog post: Easily download files from the Open Science Framework with Papercheck daniellakens.blogspot.com/2025/07/easi...

Downloading all files in an OSF project can be a hassle. Not anymore, with Papercheck! Just run:

osf_file_download("6nt4v")