I am starting a series of essays called Arbitrary yet Reasonable. It is about the many defensible decisions behind every scientific finding: which instruments, which statistical models, and which vari...

roxygen2 8.0.0 is now on CRAN, with first-class support for S7, a bunch of R6 improvements, a new configuration style, and a slimmer dependency footprint.

PsychArchives is a disciplinary repository for psychological science and neighboring disciplines.

From Piltdown Man to the Stanford prison experiment, many famous scientific discoveries have been exposed as hoaxes or distortions

Psychotherapies have been found effective in the treatment of most mental disorders. However, substantial improvements are still much needed, and many innovations of therapies are currently being dev...

YouTube video by BAMM

If you share one single thing of our team in 2026—on social media or per email with your colleagues—please let it be this machine learning competition. It was half a decade of work to get here, especi...

The Patient Health Questionnaire-9 (PHQ-9) is a widely used tool for assessing depressive symptom severity and as a screening tool in the diagnosis of major depression. Designed as both a diagnostic i...

Background: Psychological interventions are developed and tested as packages of multiple components. Identifying active ingredients requires access to detailed intervention descriptions, such as from ...

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My previous two blogs focused on how to do a specification curve analysis (SCA) using the R package “specr” (here) and the Stata program “speccurve” (here). Both blogs provided line-by-line explana…

The varying sizes of effects in published meta-analyses on digital interventions for depression prompt questions about their efficacy.A systematic sea…

Brief summary of our new paper on the personal-internal reification of p-factor causes with Merlijn Olthof and Anna Lichtwarck-Aschoff