Marius Mercier
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mariusmercier.bsky.social
Marius Mercier
@mariusmercier.bsky.social
PhD student in Cognitive Psychology | ENS-PSL. Currently working on the dynamics of impression formation, reputation management, and how it impacts our behavior.

https://mariusmercier.github.io
Hi, many thanks for sharing this!

I've tested across several device (pc with low quality camera and a recent iphone). On the iphone it works well, but on the pc it works only on Firefox but it doesn't work on Brave (I tried several times). I don't understand why
November 24, 2025 at 3:38 PM
November 20, 2025 at 9:14 AM
Thanks Tanay !!
November 14, 2025 at 10:55 AM
📄 Preprint: doi.org/10.31234/osf...
💾 Data, code, materials, and preregistrations: osf.io/aecyr/files?...

Huge thanks to my co-authors, all senior authors with equal contribution: @oliviermorin.bsky.social, @hugoreasoning.bsky.social, @tadegquillien.bsky.social
OSF
doi.org
November 13, 2025 at 5:16 PM
⚙️ We analyze behavior both at the aggregated level and at the trial level, showing that participants’ accuracy is not merely a wisdom-of-crowds artifact.

🤖 Our Bayesian model outperforms several plausible heuristic models and explains ~90% of the variance at the aggregated level.
November 13, 2025 at 5:16 PM
More in the paper:

📊 We combine a rich behavioral dataset (N=1,916; 113,400 knowledge-attribution judgments; 2,960 search choices) with a large and diverse stimulus set (N >1200).
November 13, 2025 at 5:16 PM
📌 The same Bayesian framework explains information search. Participants flexibly queried new information in ways that match an optimal information-theoretic search model.
November 13, 2025 at 5:16 PM
📌 A Bayesian model best explains these inferences. Participants’ judgments are best described by a Bayesian model that rationally integrates new evidence with prior expectations about others’ competence.
November 13, 2025 at 5:16 PM
Main findings:

📌 People can accurately predict what others know from very limited information. From a single observed answer, participants could predict the probability that someone would know another trivia question with striking accuracy!
November 13, 2025 at 5:16 PM
After seeing an individual’s performance on a trivia question, participants had to either:
- predict the individual’s ability to answer other trivia questions from the same theme, or
- select which information would be most diagnostic for inferring an individual’s competence.
November 13, 2025 at 5:16 PM
In our new preprint (doi.org/10.31234/osf...), we examine how people infer others’ competence from sparse evidence, and the computational principles underlying these judgments.

We tested participants’ inferences on two tasks requiring fine-grained estimations. 👇
OSF
doi.org
November 13, 2025 at 5:16 PM
Many thanks!
October 25, 2025 at 8:57 AM
Thanks for sharing.
I now need to debunk the misinformation I shared yesterday 😅
October 17, 2025 at 7:15 AM
Very cool!
October 17, 2025 at 7:07 AM
Seems exciting! 👀
October 15, 2025 at 1:41 PM