Abstract: Accurately measuring social norms is crucial both for explaining cooperation and prosociality and for designing effective policy measures that support these. While established laboratory-based approaches represent “gold-standard” approaches, their practicality and widespread use are limited by the restrictions involved in their implementation. In contrast, non-incentivised survey measures are simple and widely used yet remain unvalidated, leaving it unclear what they truly capture. We address this gap by validating a popular set of non-incentivised measures against incentivised benchmarks across two diverse contexts—one WEIRD (Italy) and one non-WEIRD (India)—using student and general-population samples (N≈1,400) in laboratory and lab-in-the-field environments. Every measure is validated in seven settings representing a range of interaction domains including cooperation (e.g. Public Goods Game, Dictator Game). From these results, we assemble a menu of validated survey measures, highlighting their respective strengths and offering guidance for best practice across different research contexts and constraints.

This week's Cooperation Colloquium:

Aron Szekely @aronszekely.bsky.social

Measuring social norms with surveys

Date: Friday, April 24
Time: 15:00 UTC+2 (Vienna) / 9am ET (NYC)

Sign up: list.ku.dk/postorius/li...

I don't know where that figure is from, but it's not from the paper reporting the reproducibility results, because that paper did not assess replicability (a parallel paper did).

If frozen breakfast is what your aiming for, definitely 😅

I once got peanut butter-flavoured frozen yogurt with mochi toppings.

Tasted like frozen breakfast -- rice cakes with peanut butter.

Kümmert sich deine Buchhaltung eigentlich auch um die Wortwitzkasse?

I do occasionally, mostly when I want to teach from the book.

Of course, I buy my physical books from an independent bookshop.

Shape the future of social science as a PhD student of machine learning-informed theory construction, based on patterns in high-frequency longitudinal data! You will be part of vibrant communities like the INSIGHT Lab, Theory Methods Society, and Tilburg Experience Sampling Center

tiu.nu/23721

This strikes me as a terrible idea. The US government is not trying to enhance scientific integrity, no matter how they are framing their attacks on science. Treating their concerns and efforts as legitimate undermines genuine reform efforts.

I've come see supervising research projects by secondary school students as unethical, to the point where I think faculty should be banned from doing it. It's such an obvious amplifier of individual privilege, and I can't see how it benefits science.

Today's Cooperation Colloquium with @saptarshi.bsky.social is coming up in a few hours

Really funny for Haidt to accuse others of rigging things in their favour when his own data have never fit his favoured five-factor solution. It's astonishing how long-lasting a theory can be when it is refuted by the same papers in which it is introduced.

This one is great for covering dyadic data, too. Used that for the my dissertation!

Ha, I drew on that paper when I wrote my own paper using Bayesian MELSM. Bit too advanced for my student, I fear.

Any recommendations for a (recent-ish) workflow or tutorial for mixed-effects modelling of experience sampling data in R? Looking for something to hand to my master's student.

Somewhat funny how the arch-urbanists start complaining about having to walk a whole mile (!) in New York City (!!) because they illegally parked their car.

Hey all! Been away from BSky for a while but this Friday I am giving a talk on our latest PNAS Nexus paper on repeated games! We model situations where players, instead of acting simultaneously, act in order. We study the status of well-known equilibrium strategies when simultaneity is broken.

Abstract: Repeated interaction is a key mechanism driving the evolution of cooperation, generosity, extortion, and other social behaviors. These behaviors are typically studied using two-player repeated games, where the two players act simultaneously in every round. In this paper, we begin with a standard two-action repeated game, but transform it into a leader–follower game. We do this by forcing one player to indicate their impending move, or to openly commit first in each round. We show that this simple transformation provides new and useful analytical insights. In particular, we use this transformation to derive expressions for the main classes of simultaneous-move Nash equilibria of memory-1, when payoffs are discounted. We show that these equilibria also remain stable under the leader–follower structure. We prove that this reassuring property does not always extend to games with more than two actions or to equilibrium strategies with longer memory. Overall, we establish a novel connection between repeated simultaneous-move games and repeated leader–follower games in evolutionary game theory. This approach offers fruitful means of investigating how prediction and anticipation play a role in stable social behavior.

This week's Cooperation Colloquium:

Saptarshi Pal (Harvard)

From simultaneous to leader-follower play in direct reciprocity

Date: April 10
Time: 15:00 UTC+2 (Vienna) / 9am ET (NYC)

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We are hiring PhD Position in Judgment & Decision Making At a Glance Topic: Human-AI Interaction & Cognitive Biases Locations: VŠE Prague (2 years) + Maastricht University (2 years) Funding: Fully funded (4-year pr...

Do you want to do a PhD in Judgment and Decision Making in two beautiful European locations on human-AI interaction?

Well have I got news for you.

@bahniks.bsky.social and I are recruiting a candidate to start around September 2026.

See here: decisionlab.vse.cz/english/we-a...

I am less interested here in what documentaries convey about the science than in how people respond to them. To me, it seems that many people hold contradictory beliefs about heritability, which has important policy consequences (e.g. right to know biological parents)

A common answer is that bullies may be individually brilliant, but their contributions are outweighed by holding back the contributions of others. I've long thought that to be a bit of a cop out, and in Trivers' case, it's at least not obviously true.

This is worth a read even if you're not into evolutionary theory. Trivers' work was as obviously brilliant as his reported behaviour was awful. It forces us to consider how much space academia should give to people whose behaviour towards others is frequently hurtful.

This is something people will absolutely refuse to accept -- until they see a documentary about twins reared apart. (Actually, that suggests an interesting intervention...)

Today on the Cooperation Colloquia:

I did have a look at Nat Comm's website, their volume in biomedical research is very high, so this may check out. I guess I'd thought them to be more selective because the social science they publish tends to be fairly high quality.

Scientific Reports is just Frontiers for people who think their work should've been published in Nature.

In my experience, their editors frequently have no clue about the research they are handling and their communication is shoddy. I no longer review for them.

Ok, after a look at their website, maybe Nature Communications actually does have that publication volume. Still, when I've reviewed for them, it's never felt pay-to-publish the way Sci Rep does.

This doesn't look right. Does this analysis conflate Nature Communications and NPG's disciplinary journals like Communications Psychology? Those are very different journals in terms of selectiveness.

FindAPhD : 4-year PhD / Associate Lecturer positions in the School of Psychology & Neuroscience at University of St Andrews Apply for a PhD: 4-year PhD / Associate Lecturer positions in the School of Psychology & Neuroscience at University of St Andrews

We're hiring a number of PhD students in psychology and neuroscience at St Andrews.

Positions are for four years. UK applicants only, unfortunately. Deadline April 13.

I'm eligible as a supervisor -- do reach out if you'd like to work with me.

www.findaphd.com/phds/program...

Abstract: Social norms are unwritten rules that guide human behavior and social interaction. They play a central role in promoting cooperation and maintaining cultural diversity. Yet because norms pressure people to do what others do, they may also sustain practices that are inefficient or harmful. In this talk, I present insights from a mathematical model and a field study that together examine whether and how such norms can persist. The model challenges the idea that arbitrary or harmful norms can be maintained solely through social pressure. It shows that norms with continuously varying behavioral options cannot be maintained at ecologically or psychologically suboptimal equilibria, suggesting that norms adapt more readily than previously assumed. I then present evidence from a field study among the Derung, small-scale horticulturalists in Yunnan, China. Derung farmers continued to follow a traditional cooperative farming harvest division norm after market integration. They did so even though they recognized its lower ecological payoff and expected no social disapproval for deviating from it. Rather than payoff calculations, Derung farmers adhered to the norm out of a desire to follow tradition and common practice. However, five years later the norm had changed, consistent with the model’s prediction that norms with continuously varying options eventually adapt to ecological conditions.

This week's Cooperation Colloquium:

Minhua Yan @minhuayan.bsky.social @iast.fr

The persistence and adaptation of social norms: Theory and field evidence

Date: March 27
Time: 15:00 UTC+1 (Vienna) / 10 am ET (NYC)

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The inimitable Amalia Bastos is accepting applications for PhD students, through @standrewspsyneuro.bsky.social @uniofstandrews.bsky.social

4-year funding is available for students with the right to work in the UK: www.findaphd.com/phds/program...

Awesome project, dreamy place, stellar mentor