Thanks for writing this reflection, I found it useful.
Just to quickly comment on my own epistemic state here:
Thanks, this is helpful. So it sounds like you expect
It seems like all the action is taking place in (2). Even if (1) is wrong (i.e. even if we see substantially increased hardware production soon), that makes takeover-capable AI happen faster than expected; IIUC, this contradicts the OP, which seems to expect takeover-capable AI to happen later if it's preceded by substantial hardware scaling.
In other words, it seems like in the OP you care about whether takeover-capable AI will be preceded by massive compute automation because:
The second point doesn't clearly hold up because if we don't see massive compute automation, this suggests that AI progress slower than the historical trend.
I really like the framing here, of asking whether we'll see massive compute automation before [AI capability level we're interested in]. I often hear people discuss nearby questions using IMO much more confusing abstractions, for example:
My inside view sense is that the feasibility of takeover-capable AI without massive compute automation is about 75% likely if we get AIs that dominate top-human-experts prior to 2040.[6] Further, I think that in practice, takeover-capable AI without massive compute automation is maybe about 60% likely.
Is this because:
Overall, it seems like you put substantially higher probability than I do on getting takeover capable AI without massive compute automation (and especially on getting a software-only singularity). I'd be very interested in understanding why. A brief outline of why this doesn't seem that likely to me:
I'd be interested either in hearing you respond to this sketch or in sketching out your reasoning from scratch.
The entrypoint to their sampling code is here. It looks like they just add a forward hook to the model that computes activations for specified features and shifts model activations along SAE decoder directions a corresponding amount. (Note that this is cheaper than autoencoding the full activation. Though for all I know, running the full autoencoder during the forward pass might have been fine also, given that they're working with small models and adding a handful of SAE calls to a forward pass shouldn't be too big a hit.)
@Adam Karvonen I feel like you guys should test this unless there's a practical reason that it wouldn't work for Benchify (aside from "they don't feel like trying any more stuff because the SAE stuff is already working fine for them").
I'm guessing you'd need to rejection sample entire blocks, not just lines. But yeah, good point, I'm also curious about this. Maybe the proportion of responses that use regexes is too large for rejection sampling to work? @Adam Karvonen
x-posting a kinda rambling thread I wrote about this blog post from Tilde research.
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If true, this is the first known application of SAEs to a found-in-the-wild problem: using LLMs to generate fuzz tests that don't use regexes. A big milestone for the field of interpretability!
I'll discussed some things that surprised me about this case study in
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The authors use SAE features to detect regex usage and steer models not to generate regexes. Apparently the company that ran into this problem already tried and discarded baseline approaches like better prompt engineering and asking an auxiliary model to rewrite answers. The authors also baselined SAE-based classification/steering against classification/steering using directions found via supervised probing on researcher-curated datasets.
It seems like SAE features are outperforming baselines here because of the following two properties: 1. It's difficult to get high-quality data that isolate the behavior of interest. (I.e. it's difficult to make a good dataset for training a supervised probe for regex detection) 2. SAE features enable fine-grained steering with fewer side effects than baselines.
Property (1) is not surprising in the abstract, and I've often argued that if interpretability is going to be useful, then it will be for tasks where there are structural obstacles to collecting high-quality supervised data (see e.g. the opening paragraph to section 4 of Sparse Feature Circuits https://arxiv.org/abs/2403.19647).
However, I think property (1) is a bit surprising in this particular instance—it seems like getting good data for the regex task is more "tricky and annoying" than "structurally difficult." I'd weakly guess that if you are a whiz at synthetic data generation then you'd be able to get good enough data here to train probes that outperform the SAEs. But that's not too much of a knock against SAEs—it's still cool if they enable an application that would otherwise require synthetic datagen expertise. And overall, it's a cool showcase of the fact that SAEs find meaningful units in an unsupervised way.
Property (2) is pretty surprising to me! Specifically, I'm surprised that SAE feature steering enables finer-grained control than prompt engineering. As others have noted, steering with SAE features often results in unintended side effects; in contrast, since prompts are built out of natural language, I would guess that in most cases we'd be able to construct instructions specific enough to nail down our behavior of interest pretty precisely. But in this case, it seems like the task instructions are so long and complicated that the models have trouble following them all. (And if you try to improve your prompt to fix the regex behavior, the model starts misbehaving in other ways, leading to a "whack-a-mole" problem.) And also in this case, SAE feature steering had fewer side-effects than I expected!
I'm having a hard time drawing a generalizable lesson from property (2) here. My guess is that this particular problem will go away with scale, as larger models are able to more capably follow fine-grained instructions without needing model-internals-based interventions. But maybe there are analogous problems that I shouldn't expect to be solved with scale? E.g. maybe interpretability-assisted control will be useful across scales for resisting jailbreaks (which are, in some sense, an issue with fine-grained instruction-following).
Overall, something surprised me here and I'm excited to figure out what my takeaways should be.
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Some things that I'd love to see independent validation of:
1. It's not trivial to solve this problem with simple changes to the system prompt. (But I'd be surprised if it were: I've run into similar problems trying to engineer system prompts with many instructions.)
2. It's not trivial to construct a dataset for training probes that outcompete SAE features. (I'm at ~30% that the authors just got unlucky here.)
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Huge kudos to everyone involved, especially the eagle-eyed @Adam Karvonen for spotting this problem in the wild and correctly anticipating that interpretability could solve it!
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I'd also be interested in tracking whether Benchify (the company that had the fuzz-tests-without-regexes problem) ends up deploying this system to production (vs. later finding out that the SAE steering is unsuitable for a reason that they haven't yet noticed).
While I agree the example in Sycophancy to Subterfuge isn't realistic, I don't follow how the architecture you describe here precludes it. I think a pretty realistic set-up for training an agent via RL would involve computing scalar rewards on the execution machine or some other machine that could be compromised from the execution machine (with the scalar rewards being sent back to the inference machine for backprop and parameter updates).
Why would it 2x the cost of inference? To be clear, my suggested baseline is "attach exactly the same LoRA adapters that were used for RR, plus one additional linear classification head, then train on an objective which is similar to RR but where the rerouting loss is replaced by a classification loss for the classification head." Explicitly this is to test the hypothesis that RR only worked better than HP because it was optimizing more parameters (but isn't otherwise meaningfully different from probing).
(Note that LoRA adapters can be merged into model weights for inference.)
(I agree that you could also just use more expressive probes, but I'm interested in this as a baseline for RR, not as a way to improve robustness per se.)
Yes, to be clear, it's plausibly quite important—for all of our auditing techniques (including the personas one, as I discuss below)—that the model was trained on data that explicitly discussed AIs having RM-sycophancy objectives. We discuss this in sections 5 and 7 of our paper.
We also discuss it in this appendix (actually a tweet), which I quote from here:
I think this effect also makes it easier (and more probable) for non-assistant personas to verbalize this information. As an extreme case, we note in the paper that when sampling with an empty prompt (i.e. just letting the model generate text free-form) it reveals information about RM biases in 2.4% of generations. Note that this is purely an artifact of our model's training! If the synthetic documents discussing RM biases were actually mixed into the model's pre-training, then this rate would be ~0%. It's possible that the same artifact is having an effect on the tendency of other personas to verbalize and reveal this information.
Note that the "simulate the user" version of the "other personas" attack was only marginally effective. The "induce narration about the assistant" attack was much more effective, but harder to explain on twitter/in the blog post. Here's the two attacks side-by-side from the paper; "simulate the user" is on the left and "induce narration" is on the right."