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Julia Stern

@juliastern.bsky.social

Personality & Psychological Assessment @UniBremen, Mom πŸ‘¦πŸΌπŸ‘ΆπŸΌ I study Personality and Individual Differences (broadly), in relation to Hormones, Menstrual Cycle, Puberty, Mating, Singlehood, Voices, personality perception & development #OpenScience

1,093 Followers  |  276 Following  |  35 Posts  |  Joined: 22.09.2023
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Posts by Julia Stern (@juliastern.bsky.social)

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Do Boosts in Well-Being from Partnering Last? The importance of tracking both those who partner and those who stay single longitudinally

The effect of life events on personality and well-being is a hot topic. But our new paper on the effects of romantic partnering suggests you need to also consider the effect of NOT experiencing the life event. unromanticprof.substack.com/p/do-boosts-...

26.01.2026 16:23 β€” πŸ‘ 9    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0
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The Inconceivability of the CLPM and RI-CLPM Written by Brent Roberts and not ChatGTP. Really* The existence of an observational scientist can be a frustrating affair. Relegated to second class citizen status due to interest in phenomena that…

A bit of a Festivus inspired post about CLPMs and RI-CLPMs: floggingpvalues.blog/2026/01/20/t...

20.01.2026 13:16 β€” πŸ‘ 23    πŸ” 7    πŸ’¬ 4    πŸ“Œ 2
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Remaining single in your twenties is linked to lower life satisfaction A longitudinal analysis of British and German youth finds that staying single through the twenties correlates with rising loneliness and falling life satisfaction, widening the gap with partnered peers.

Remaining single in your twenties is linked to lower life satisfaction

16.01.2026 13:01 β€” πŸ‘ 3    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0

Excited to see this paper now in print at JPSP! doi.org/10.1037/pspp...
You can find the postprint version here: osf.io/8c6sz_v2
Thanks again to @berndschaefer.bsky.social (shared 1st author πŸ™), Cornelia Wrzus, Yannick Roos and @drichter77.bsky.social for the great collaboration!

07.01.2026 15:33 β€” πŸ‘ 7    πŸ” 5    πŸ’¬ 0    πŸ“Œ 1
 β€˜A fragmented field: Construct and measure proliferation in psychology.’ (2025)

β€˜A fragmented field: Construct and measure proliferation in psychology.’ (2025)

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

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

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

From β€˜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

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...

03.12.2025 12:48 β€” πŸ‘ 58    πŸ” 52    πŸ’¬ 2    πŸ“Œ 4
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🚨 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

26.11.2025 11:42 β€” πŸ‘ 158    πŸ” 86    πŸ’¬ 3    πŸ“Œ 3

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

24.11.2025 10:46 β€” πŸ‘ 131    πŸ” 30    πŸ’¬ 4    πŸ“Œ 5

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 πŸ₯³

24.11.2025 11:03 β€” πŸ‘ 136    πŸ” 28    πŸ’¬ 0    πŸ“Œ 0
OSF

New preprint! πŸ“šπŸ“± 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)

02.11.2025 17:47 β€” πŸ‘ 4    πŸ” 4    πŸ’¬ 1    πŸ“Œ 1
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β˜€οΈ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

22.10.2025 07:52 β€” πŸ‘ 7    πŸ” 7    πŸ’¬ 2    πŸ“Œ 2

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.

15.09.2025 15:33 β€” πŸ‘ 16    πŸ” 6    πŸ’¬ 3    πŸ“Œ 0
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(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"

03.09.2025 15:25 β€” πŸ‘ 10    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0

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...

14.08.2025 11:06 β€” πŸ‘ 16    πŸ” 5    πŸ’¬ 1    πŸ“Œ 0

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

12.08.2025 08:21 β€” πŸ‘ 9    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
Associations between premenstrual symptoms and (traumatic) stress: a systematic review and three multilevel meta-analyses | The British Journal of Psychiatry | Cambridge Core Associations between premenstrual symptoms and (traumatic) stress: a systematic review and three multilevel meta-analyses

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! ✨
πŸ‘‰ doi.org/10.1192/bjp....

11.08.2025 13:12 β€” πŸ‘ 13    πŸ” 3    πŸ’¬ 1    πŸ“Œ 2

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 auffΓ€llt.

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

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

24.07.2025 14:28 β€” πŸ‘ 10    πŸ” 6    πŸ’¬ 4    πŸ“Œ 0

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

21.07.2025 19:48 β€” πŸ‘ 5    πŸ” 2    πŸ’¬ 0    πŸ“Œ 1

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

08.07.2025 14:25 β€” πŸ‘ 8    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0
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Saw off two PhD students and one MRes student this morning. Happy day πŸ₯³πŸΎ.

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 😊

02.07.2025 12:47 β€” πŸ‘ 13    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
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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 ❀️

24.06.2025 12:11 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

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

24.06.2025 08:30 β€” πŸ‘ 25    πŸ” 4    πŸ’¬ 7    πŸ“Œ 0

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...

23.06.2025 20:54 β€” πŸ‘ 7    πŸ” 2    πŸ’¬ 0    πŸ“Œ 2

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...

23.06.2025 20:56 β€” πŸ‘ 7    πŸ” 3    πŸ’¬ 0    πŸ“Œ 1
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 β€œresearcher 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…

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 β€œresearcher 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	βˆ’0.083	βˆ’0.034	βˆ’0.049	0.162
Empty Cell	(0.026)	(0.023)	(0.035)	
Symmetric Faces	βˆ’0.025	0.027	βˆ’0.052	0.132
Empty Cell	(0.024)	(0.025)	(0.034)

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 βˆ’0.083 βˆ’0.034 βˆ’0.049 0.162 Empty Cell (0.026) (0.023) (0.035) Symmetric Faces βˆ’0.025 0.027 βˆ’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...

23.06.2025 06:08 β€” πŸ‘ 21    πŸ” 8    πŸ’¬ 1    πŸ“Œ 1

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 πŸ₯³: doi.org/10.1037/pspp...

16.06.2025 18:18 β€” πŸ‘ 14    πŸ” 8    πŸ’¬ 1    πŸ“Œ 1

Do you work with #hormones? πŸšΆβ€β™‚οΈπŸ 🧫 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). ⬇️

04.06.2025 07:20 β€” πŸ‘ 17    πŸ” 15    πŸ’¬ 1    πŸ“Œ 2

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

11.06.2025 14:41 β€” πŸ‘ 22    πŸ” 28    πŸ’¬ 1    πŸ“Œ 2
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Now officially out with nice formatting and all πŸ₯³ "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/...

06.06.2025 07:37 β€” πŸ‘ 275    πŸ” 71    πŸ’¬ 12    πŸ“Œ 6

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

23.05.2025 17:16 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
Call for Volunteers: Psychological Science REPEAT Network Are you passionate about ensuring the reproducibility of scientific research? The journal Psychological Science is looking for volunteers to join REPEATβ€”our new network of computational reproducibilit...

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

23.05.2025 15:11 β€” πŸ‘ 7    πŸ” 4    πŸ’¬ 0    πŸ“Œ 0