Constanza Fierro

Postdoc @coastalcph and @MATSprogram fellow doing NLP things. Ex SWE @Google and student @dccuchile. I also like sports, photography, and reading.

[Constanza Fierro @constanzafierro]

@yoavgo Yeah! We did some experiments in this work where we find that bias only fine tuning generalizes better than activation steering for behavior modifications https://t.co/enWCxfz9Z8

[Constanza Fierro @constanzafierro]

I’m presenting this work today at #ICLR2026 at 3:15pm in Pavilion 4 #3914

Come say hi! ☺️

[Constanza Fierro @constanzafierro]

Can we find weight directions to modify LLM's behaviors?

Our new paper proposes contrastive weight steering, an alternative to activation steering for modifying behaviors using small narrow distribution data 🕹️

��👇

[David Bau @davidbau]

At the #Neurips2025 mechanistic interpretability workshop I gave a brief talk about Venetian glassmaking, since I think we face a similar moment in AI research today.

Here is a blog post summarizing the talk:

https://t.co/LSwBf9XQzE

[Constanza Fierro @constanzafierro]

@ESRogs @DanielCHTan97 We actually tried this as a baseline in the experiments and for some behaviors it works, but for others it fails completely (steering towards non-sycophancy)

[Constanza Fierro @constanzafierro]

@DanielCHTan97 Thanks for the shout out! Link to the thread in case anyone wants to check it out

https://t.co/tQZ1SW5vdV

[Constanza Fierro @constanzafierro]

Can we find weight directions to modify LLM's behaviors?

Our new paper proposes contrastive weight steering, an alternative to activation steering for modifying behaviors using small narrow distribution data 🕹️

��👇

[Constanza Fierro @constanzafierro]

@Prakucho Cool! We missed this connection. We’ll add the citation in the next arXiv version 😄

[Constanza Fierro @constanzafierro]

Can we find weight directions to modify LLM's behaviors?

Our new paper proposes contrastive weight steering, an alternative to activation steering for modifying behaviors using small narrow distribution data 🕹️

🧵👇

[Constanza Fierro @constanzafierro]

@Butanium_ Greatest common divisor

[Constanza Fierro @constanzafierro]

Blogpost: https://t.co/QaccMlAYpC

[Constanza Fierro @constanzafierro]

Check out the paper and blogpost for more details:

Paper: https://t.co/enWCxfzHOG