nnterp by @butanium.bsky.social is now part of the NDIF ecosystem! nnterp standardizes transformer naming conventions, includes built-in best practices for common interventions, and is perfectly compatible with original HF model implementations. Learn more: ndif-team.github.io/nnterp/

Very cool analysis by Arnab which cover the mechanisms used for retrieval both when your query is before or after the text!

A very important paper led by Julian! Tldr: we show that your Narrow Finetuning is showing and might not be a realistic setup to study!

To say it out loud: @jkminder.bsky.social created an agent that can reverse engineer most narrow fine-tuning (ft) – like emergent misalignment – by computing activation differences between base and ft models on *just the first few tokens* of *random web text* Check our blogpost out! 🧵

GPT is being asked to be both one mind and to also segment its understanding into many different minds, this incentivizes the model to learn to correct for its own perspective when mimicking the generator of individual texts so it doesn't know too much, to know self vs. other in minute detail.

This Friday NEMI 2025 is at Northeastern in Boston, 8 talks, 24 roundtables, 90 posters; 200+ attendees. Thanks to goodfire.ai/ for sponsoring! nemiconf.github.io/summer25/ If you can't make it in person, the livestream will be here: www.youtube.com/live/4BJBis...

Excited to share our first paper replication tutorial, walking you through the main figures from "Do Language Models Use Their Depth Efficiently?" by @robertcsordas.bsky.social 🔎 Demo on Colab: colab.research.google.com/github/ndif-... 📖 Read the full manuscript: arxiv.org/abs/2505.13898

With @butanium.bsky.social and @neelnanda.bsky.social we've just published a post on model diffing that extends our previous paper. Rather than trying to reverse-engineer the full fine-tuned model, model diffing focuses on understanding what makes it different from its base model internally.

Our mech interp ICML workshop paper got accepted to ACL 2025 main! 🎉 In this updated version, we extended our results to several models and showed they can actually generate good definitions of mean concept representations across languages.🧵

New alignment theory paper! We present a new scalable oversight protocol (prover-estimator debate) and a proof that honesty is incentivised at equilibrium (with large assumptions, see 🧵), even when the AIs involved have similar available compute.

We'll be presenting at the #ICLR sparsity in LLMs workshop today (Sunday 27th) at 4:30 pm in Hall 4 #7!

Want to explore cool chat related crosscoder latents? With @jkminder.bsky.social, we made a demo that supports both loading our max activating examples AND running the crosscoder with your own prompt to collect the activations of specific latents! Send us the cool latents you find! dub.sh/ccdm

In our most recent work, we looked at how to best leverage crosscoders to identify representational differences between base and chat models. We find many cool things, e.g., a knowledge boundary, a detailed info and a humor/ joke detection latent.

New paper w/@jkminder.bsky.social & @neelnanda.bsky.social What do chat LLMs learn in finetuning? Anthropic introduced a tool for this: crosscoders, an SAE variant. We find key limitations of crosscoders & fix them with BatchTopK crosscoders This finds interpretable and causal chat-only features!🧵

Very cool work that introduces "concept heads" that copy meanings from one token to another. I love that our activation-based analysis of multilingual representation has now additional insight from weight space analysis: bsky.app/profile/sfeu...

Want to get into alignment research? Alex Cloud & I mentor *Team Shard*, responsible for gradient routing, steering vectors, MELBO, and a new unlearning technique (TBA) :) We discover new research subfields. Apply for mentorship this summer at forms.matsprogram.org/turner-app-8

Excited about recent reasoning models? What is happening under the hood? Join ARBOR: Analysis of Reasoning Behaviors thru *Open Research* - a radically open collaboration to reverse-engineer reasoning models! Learn more: arborproject.github.io 1/N

As part of opening my new round of MATS applications, I took this as an excuse to write up which research discussions I'm currently just excited about, and recent updates I've made - I thought this might be of more general interest! x.com/NeelNanda5/...

LLM agents will be a very big deal, bringing many weird new forms of reward hacking and other subtle failures This great GDM safety paper shows that myopically optimising for plans that an overseer approves of, rather than outcomes, reduces these issues while performing well! x.com/davlindner/...

Do you have a great experiment that you want to run on Llama 405b but not enough GPUs? 🚨 #NDIF is opening up more spots in our 405b pilot program! Apply now for a chance to conduct your own groundbreaking experiments on the 405b model. Details: 🧵⬇️

Can we understand and control how language models balance context and prior knowledge? Our latest paper shows it’s all about a 1D knob! 🎛️ arxiv.org/abs/2411.07404 Co-led with @kevdududu.bsky.social - @niklasstoehr.bsky.social , Giovanni Monea, @wendlerc.bsky.social, Robert West & Ryan Cotterell.