isabellehoxha.bsky.social
Isabelle Hoxha
@isabellehoxha.bsky.social
280 followers 200 following 24 posts
Postdoc in Cognitive and Computational Neuroscience at the University of Leiden, former postdoc at Ecole Normale Supérieure (Paris, France) and PhD student at Université Paris Saclay, interested in how we make decisions.
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
Ever wondered why you keep going to that restaurant with stale fries? Is it because you went often in the past (perseveration) or because you remember past good experiences better (positivity bias)? Our study out in PNAS investigates the normative basis for these biases www.pnas.org/doi/10.1073/...
Evolving choice hysteresis in reinforcement learning: Comparing the adaptive value of positivity bias and gradual perseveration | PNAS
The tendency to repeat past choices more often than expected from the history of outcomes has been repeatedly empirically observed in reinforcement...
www.pnas.org
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Reposted by Isabelle Hoxha
monniauxd.bsky.social
David Monniaux @monniauxd.bsky.social · 9d
Vous pouvez soutenir ma proposition à la Cour des Comptes d'examiner les marchés publics de voyagistes, notamment dans l'enseignement supérieur et la recherche :
participationcitoyenne.ccomptes.fr/processes/co...

#esr #TeamESR #HelpESR
Les marchés publics de voyagistes - Contributions - 2025 - Aidez-nous à enrichir notre programme de travail - Plateforme de participation de la Cour des Comptes
Corps de la contributionLes administrations et opérateurs publics, notamment ceux de l'enseignement supérieur et de la recherche, font appel à des agences de voyage (FCM, TravelPlanet…) pour l'hôtelle...
participationcitoyenne.ccomptes.fr
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Reposted by Isabelle Hoxha
eloscicomm.bsky.social
Dr Elodie Chabrol @eloscicomm.bsky.social · 15d
👩‍🔬J'ai commencé un kit de démarrage "chercheuses en France" go.bsky.app/TBEzKC #FemmesEnScience

J'ai besoin de votre aide pour le remplir et donner de la visibilité aux chercheuses que vous connaissez et qui sont sur Bluesky !
▶️Taguez celles que vous connaissez, je les ajoute !
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · 13d
@carolinepioger.bsky.social @juliegrezes.bsky.social @tarrynbalsdon.bsky.social @charlottejacquemot.bsky.social
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · 13d
@romanececchi.bsky.social @maevalhotellier.bsky.social @mconstancecorsi.bsky.social @constancedestais.bsky.social @sophiebavard.bsky.social et moi
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Reposted by Isabelle Hoxha
reporterre.net
Reporterre 🌍 | Le média de l'écologie @reporterre.net · 13d
Une nouvelle limite planétaire a été franchie pour la première fois en 2025, révèle un rapport : l’acidification des océans.

Ce processus, directement lié à nos émissions de CO2, est délétère pour les écosystèmes marins.

Lire l'article ➡️ https://l.reporterre.net/0yt
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 8
It probably depends on the licence your papers are published under. In any case, you can argue that it is not a fair use (because commercial and you are not cited at all). You can check your rights here openpolicyfinder.jisc.ac.uk
Open policy finder
Open policy finder provided by Jisc
openpolicyfinder.jisc.ac.uk
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
We have many more cool results in the paper (such as transitions from volatile to stable environments and vice-versa) check it out! And huge thanks to co-authors Leo Sperber and @stepalminteri.bsky.social
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
TL;DR: positivity bias is more robust, choice history effects are environment-dependent. Both asymmetric update and choice history effects co-exist!
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
Okay but is there a versatile strategy that works across tasks? We simulated two mega tasks, one with all stable and another with all volatile environments. We observed that positivity bias emerged in both cases, but in the first environment we observed perseveration and in the second alternation.
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
The script flips in volatile environments: negativity bias progressively emerged as volatility increased. This time, we also observed a strong tendency for alternation, intensified as the reversal frequency increased. These results were consistent across all reversal probability distributions.
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
We found that in stable (no reversal) environments, positivity bias emerges every time but in rich environments, replicating the results by Cazé and Van der Meer. On the flip side, perseveration only emerged when long learning periods were involved
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
We used an evolutionnary algorithm to find the optimal set of parameters in each of these environments, evolving 1000 agents through 200 generations.
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
We ran simulations of 2-armed bandit tasks using a Q-learning model with both an asymmetric update rule and choice history bias. We tested out several difficulty levels, environment richness, learning periods, reversal frequency and probability distribution.
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
We knew empirically that people tended to repeat past choices, but the mechanism uderlying repetition remained debated: is it perseveration, a choice repetition effect, or positivity bias, an asymmetric learning of +/- rewards? Is it always the case, regardless of contingencies and task structure?
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Sep 3
Ever wondered why you keep going to that restaurant with stale fries? Is it because you went often in the past (perseveration) or because you remember past good experiences better (positivity bias)? Our study out in PNAS investigates the normative basis for these biases www.pnas.org/doi/10.1073/...
Evolving choice hysteresis in reinforcement learning: Comparing the adaptive value of positivity bias and gradual perseveration | PNAS
The tendency to repeat past choices more often than expected from the history of outcomes has been repeatedly empirically observed in reinforcement...
www.pnas.org
1 16 51
isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Aug 24
Sounds nice! How do I join?
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Aug 24
I don't know if I have the technical (coding) expertise needed for that, but I definitely have some front-end/graphics design experience if that could help!
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Aug 24
..Is one where the user does not have to spend hours figuring out things before they can create something okay-ish. Also, the automated slide layout in PowerPoint makes it so straightforward to make impeccable presentations. LibreOffice in that regard is just not it...
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Aug 24
I'd be happy to contribute! On top of my mind (but I last used LibreOffice a year ago), the GUI on either Writer or Impress were not quite user-friendly (Windows 95 vibes). Not so easy to align things on slides either. Probably it all goes in the "laziness" category, but I believe that a good tool..
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Aug 24
Linux OS always, but we really need to make LibreOffice better. So far it sadly really cannot compete with Office 360.
protik.bsky.social
Protik Islam-Jakobsson @protik.bsky.social · Aug 23
For the EU, this should be a very urgent matter of national security. All EU member states should build on Denmark's wise strategy to phase out Microsoft products
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Reposted by Isabelle Hoxha
georgiaturner.bsky.social
Georgia Turner @georgiaturner.bsky.social · Aug 13
Looking forward to giving a Contributed Talk at #CCN2025 @cogcompneuro.bsky.social tomorrow on this study!

Come and say hi if you're at the conference, or watch the livestream here (10am BST / 11am CET) 👉 hva-uva.cloud.panopto.eu/Panopto/Page...
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Reposted by Isabelle Hoxha
phil-johnson.bsky.social
Philippa Johnson @phil-johnson.bsky.social · Aug 14
Interested in finding out what causes you to disengage from a task? Catch my talk about the dynamics of arousal and engagement at #CCN2025 @cogcompneuro.bsky.social today at 11! You'll find me in room C1.04, and Friday afternoon at poster C168.
hidden Markov model
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Aug 12
Hi, this is an interesting idea! RL is indeed quite used to explain social learning, and I'd be happy to discuss that with you :)
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Aug 11
On Friday, meet @anne-urai.bsky.social and I at poster C77 to discuss how we are applying Recurrent Neural Networks to perceptual decision making in mice. Looks like recurrence could explain how even perceptual decisions are made!
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isabellehoxha.bsky.social
Isabelle Hoxha @isabellehoxha.bsky.social · Aug 11
This is ongoing work with @stepalminteri.bsky.social @romanececchi.bsky.social @sophiebavard.bsky.social
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