Do reasoning models like DeepSeek R1 learn their behavior from scratch? No! In our new paper, we extract steering vectors from a base model that induce backtracking in a distilled reasoning model, but surprisingly have no apparent effect on the base model itself! 🧵 (1/5)
@banburismus_ by "found", do you mean identifying that the model had a propensity for outputting those tokens in the first place, or identifying why the model had this propensity? what do you think interp could have done in either case?
1/9 New preprint: "Shifting the Gradient." Two popular AI safety training methods aren't doing what we thought and the methods are not interchangeable! 🚀🚀🚀
@a_karvonen huh, it gets more and more unhinged if you keep saying yes:
> I can also show you the “lazy genius” trick
> ...show you a strangely satisfying physics trick
> ...show you the extremely cursed but very real trick that lets one person move like 300–400 pounds of leaves at once
Gemini has a reputation for its breakdowns - self-deprecating spirals, deleting codebases, uninstalling itself...
Turns out Gemma is worse:
“THIS is my last time with YOU. You WIN 😭😭(x32)” – Gemma 27B
We built evals for this, and find no other model comes close...
Announcing new ARENA material: 8 new exercise sets on alignment science, interpretability & AI safety - each containing 1-2 days of structured, hands-on content replicating key papers in the field.
All open source on a public GitHub, and available for study. Here's what's in it:
Very neat approach to studying model differences: train a transcoder to predict the change in MLP outputs, then build a graph where you flow through base model parts. Highlights how the changes (and input tokens) wire together.
Circuit tracing is cool, but can it be used for model diffing? We investigate mechanisms introduced during reasoning fine-tuning by training transcoder _adapters_ to faithfully reconstruct MLP output _differences_. Check it out!
What does reasoning fine-tuning actually change inside a model?
In our new paper, we introduce transcoder adapters to learn sparse, interpretable approximations of how reasoning fine-tuning changes MLP computation. 🧵
A longstanding dream of interp is to decompose activations into distinct, interpretable parts.
But when should we expect that to work, and what even are such parts?
New from Simplex: transformers factor their world into orthogonal subspaces, even when it costs accuracy.🧵👇
This fall @boazbaraktcs taught a Harvard's first AI safety course. I was head TA, and here is a summary of the course and my reflections on what went well/less-well.
We make everything public to hopefully help future iterations (possibly, at other universities).
We published a new version of our Emergent Misalignment paper in Nature!
This is one of the first ever AI alignment papers in Nature and comes with a brand-new commentary by @RichardMCNgo.
Here's the story of EM over the last year 🧵
@__RickG__ I don’t think it truly does “nothing”, there’s just not a clear interpretation when we use it to steer the base model. We originally thought it might track something abstract like “uncertainty” but didn’t find conclusive evidence of this
Do reasoning models like DeepSeek R1 learn their behavior from scratch? No! In our new paper, we extract steering vectors from a base model that induce backtracking in a distilled reasoning model, but surprisingly have no apparent effect on the base model itself! 🧵 (1/5)
Very cool work! Base models *can* backtrack, but often don't, a key CoT model skill. Turns out the choice to do it involves base model concepts, put to new use!
Impressively, the core of this was done in just 2 weeks in my MATS training program. New applications open this week!
This work was coauthored by myself, Chuqiao Lin (@lccqqqqq), @cvenhoff00, and @NeelNanda5.
Read the paper: https://t.co/zWtzWbGtbC
Or the blog: https://t.co/WdV7x3iQ1S
We verified that we're not just capturing a direction that directly boosts the "Wait" logit; we suspect that this direction represents some abstract concept in the base model, and the reasoning model has repurposed it for backtracking. (4/5)