Julia Stern

‘A fragmented field: Construct and measure proliferation in psychology.’ (2025)

From ‘Language models accurately infer correlations between psychological items and scales from text alone.’ (2025)

From ‘Not within spitting distance: salivary immunoassays of estradiol have subpar validity for predicting cycle phase.’ (2023)

Work in progress with cycle tracking data from the app Clue

Want to make nice graphs with me, starting next year? I'm hiring for a position at the University of Witten/Herdecke.
uni-wh.softgarden.io/job/61280592...

🚨 SynthNet is out 🚨
Researchers propose new constructs and measures faster than anyone can track. We (@anniria.bsky.social @ruben.the100.ci) built a search engine to check what already exists and help identify redundancies; indexing 74,000 scales from ~31,500 instruments in APA PsycTests. 🧵1/3

Congratulations to @simine.com well deserved winner of the Einstein Foundation Individual Award for Promoting Quality in Research 2025 🎉 www.einsteinfoundation.de/en/media/pre...

I think it's hard to overstate how much Simine has changed research practices and standards in psychology for the better, despite at times massive resistance from powerful parties with a vested interest in maintaining the status quo. Very well deserved award imho 🥳

New preprint! 📚📱 osf.io/3kpf9_v1
Did you ever stand in a bookshop and wondered who tends to buy self-help books, and whether people who buy them actually change? Here, we looked at these questions for self-help products more generally (also apps, seminars, etc.), which are a rapidly (1/3)

☀️To all Master’s & PhD students: Join the Summer School of Personality Science 2026 (July 15–19, Edinburgh) for a week of research training, mentoring & networking in personality psychology.

Template: osf.io/76ej2/files/...
Apply Nov 2-20: www.conftool.org/ssps2026

#SSPS #eapp

Is the idea that getting into a romantic relationship increases well-being a myth? A new MacLab paper says no. And I had so much to say about this work, I started a Substack: The Unromantic. Links for the paper and the Substack in replies.

(PDF) Cultural differences in the personality triad: The interplay of personality traits, situation characteristics, and behavioral states around the world PDF | Understanding the interplay of persons, situations, and behavior (the Personality Triad) is a key task of psychology. However, previous research... | Find, read and cite all the research you nee...

Very excited to share our new manuscript accepted at JPSP: "Cultural Differences in the Personality Triad: The Interplay of Personality Traits, Situation Characteristics, and Behavioral States Around the World"

Excited to share this new preprint with Simon Breil, Katharina Utesch & Mitja Back: "Predicting More Behavior More of the Time: On the Behavioral Nature of Different Personality Trait Measures" osf.io/preprints/ps...

Read our new meta-analyses paper on the connection between stress and premenstrual symptoms. Congratulations to Celine Bencker for leading this project!

How are #stress and premenstrual symptoms connected?
And are those with a #trauma history more likely to have #PMS or #PMDD? 🌩️

Our systematic review & three meta-analyses combine evidence from 66 studies to explore these questions.

Excited our work is finally out! ✨
👉 doi.org/10.1192/bjp....

I ❤️ MDPI

Schaut euch mal die Editoren dieses Special Issues an.
Dann schaut mal bei allen Artikeln auf die Autorenliste.

Und dann sagt mir, ob euch etwas auffällt.

Special Issue:
"Towards Autonomous Operation of Biologics and Botanicals"

www.mdpi.com/journal/proc...

Check out our preprint - the result of a really fun collaboration!

New MacLab paper. Do people partner up to save on rent? Apparently not.

Saw off two PhD students and one MRes student this morning. Happy day 🥳🍾.

If you want an amazing PhD of developmental body image hit up Dr Louise Hanson; for a post doc on voices I cannot recommend Dr @jrut.bsky.social highly enough.
And Joe McAdam is looking for PhD funding too 😊

a woman is smiling and holding her hand to her chest while wearing a polka dot shirt . ALT: a woman is smiling and holding her hand to her chest while wearing a polka dot shirt .

Aww you're way too kind, Victor! Thanks for all your support - you're the best and my personal star. Very grateful for knowing you ❤️

Many thanks to HBES for this recognition and congratulations to Rising Stars @mohammadatari.bsky.social @danielredhead.bsky.social @juliastern.bsky.social 💫

HBES is happy to recognize the following Rising Stars (<8 years post-PhD) for their research contributions:
Mohammad Atari: mohammadatari.com
Catherine Molho: catherinemolho.github.io
Daniel Redhead: www.rug.nl/staff/d.j.re...
Julia Stern: www.uni-bremen.de/en/pppd/team...

Congrats to HBES Rising Star Julia Stern, for her evolutionary work on personality, including its effects on well-being, mate choice, as well as the development and hormonal correlates of personality: www.uni-bremen.de/en/pppd/team...

We provide the first evidence from a randomized double-blind placebo control study of oral contraceptives on women's preferences for masculine and symmetric faces in men. We find no evidence of an effect. Similar, our correlational results testing for an association between menstrual cycle phases and facial preferences fail to reject the null hypothesis of no association, as do our estimated correlations between hormone levels and facial preferences. Although the early literature largely found support for variation in facial preferences over the menstrual cycle and with oral contraceptive use (Feinberg et al., 2008; Johnston et al., 2001; Little et al., 2002; Little et al., 2013; Penton-Voak et al., 1999; Roney & Simmons, 2008), our null results align with more recent large-sample correlational studies (Jones et al., 2018; Marcinkowska et al., 2019). One possible motivation of the hypothesis that oral contraceptives lower the preferences for facial masculinity and symmetry is in terms of the dual mating theory. In a recent review of the literature Jones et al. (2019) point out several methodological problems in the early work testing this hypothesis, such as low statistical power, and conclude that recent and methodologically stronger work fails to support the hypothesis. Our findings lend further support for their conclusions. There are also several reasons for why false positive results could have been published in the earlier literature. Low statistical power increases the probability for false positive results as well as inflated effect sizes. Many of the older studies also rely on self-reported menstrual cycle data, which is subject to mismeasurement. In addition, without pre-analysis plans there is room for the so-called “researcher degrees of freedom” (Simmons et al., 2011) to influence the analysis such that statistically significant results become more likely to be false positive ones. This can occur through excluding observations, using covariates, testing…

Table 2. The effect of OC on facial preferences. Empty Cell % Change in Facial Preferences (Follow-Up - Baseline) Difference P-value of difference Empty Cell Treatment (N = 165) Placebo (N = 168) Empty Cell Empty Cell Masculine Faces −0.083 −0.034 −0.049 0.162 Empty Cell (0.026) (0.023) (0.035) Symmetric Faces −0.025 0.027 −0.052 0.132 Empty Cell (0.024) (0.025) (0.034)

New results from one of the few preregistered, placebo-controlled combined oral contraceptive RCTs. No pill effects found on preferences for masculine or symmetric faces, no menstrual cycle effects.
N=340, so small effects may have gone undetected.
www.sciencedirect.com/science/arti...

Self-improvement, self-acceptance, and/or methods effects? Travis Miller, @chopwood.bsky.social , and @wiebkeb.bsky.social, and I examined factors that might explain personality change intervention effects - now in print at JPSP 🥳: doi.org/10.1037/pspp...

Do you work with #hormones? 🚶‍♂️🐁 🧫 Have you ever tried to share your data or worked with datasets and encountered challenges?

#NODES aims to develop a standard data format for hormones to remedy this.

Participate in our Delphi study to let us know what should be considered (open until mid June). ⬇️

Join me at the University of Witten/Herdecke for research on meta scientific topics, replication work or other fun things :-) as well as teaching some IMO wonderful students
short.sg/j/56902143

Now officially out with nice formatting and all 🥳 "Thinking clearly about age, period, and cohort effects" -- a gentle introduction to the age-period-cohort problem and how to "solve" it through various types of assumptions.

journals.sagepub.com/doi/10.1177/...

Join us at Psych Science! We're currently recruiting volunteers helping with reproducibility checks for conditionally accepted manuscripts. Important tasks - great team - recommended!

Psychological Science is looking for volunteers to join REPEAT—our new network of computational reproducibility checkers. Please join us if you have the time and skills! www.psychologicalscience.org/publications...

NODES Delphi study Are you studying hormones? We need your expertise! https://survey.questionstar.com/NODES-Delphi-round1 We are an interdisciplinary group of researchers from the field of psychoneuroendocrinology. We all have extensive experience in working with hormonal data and faced major challenges when trying to access and reuse datasets from others. We want to develop a community-driven standard data structure to facilitate data sharing and reuse in our field – and we need your input to do so. Scan the QR code to participate in our Delphi study! For more info on the project visit: https://www.nodes-pne.eu

Important #NODES updates🔥 (2/2)

We are now recruiting experts (human & animal researchers, clinicians etc) in the field of (psycho)neuroendocrinology that volunteer to fill our survey 📝
survey.questionstar.com/NODES-Delphi...

Results will be used as a starting point to develop the data structure.

Why Should You Trust Research Published in Psychological Science? - Simine Vazire, 2025

Why Should You Trust Research Published in #PsychologicalScience?

Read @simine.com's Editorial, NOW online

My editorial on how journals can earn trust.

We often use journal names as proxies for quality. This is bad bc it’s not valid. But it could be. Editors could make journal name a valid signal. And we could place value on journals that show us how they do that.

journals.sagepub.com/doi/full/10....

Valerie Baettig asks whether Tsimane women experience PMS. Answer: possibly slightly but not enough that they notice.
Also: across the 10 women cycles were super variable hormonally. More evidence we need hormone controls in cycle studies!
#ehbea #ehbea2025