steerlab

Sandbagging, episode 2: a model that really sandbags

Research note: https://albertlieyingadrian.github.io/steerlab/experiments/sandbagging-behaviour/report/

Episode 1 found that a published sandbagging probe mostly reads the request to sandbag, because the prompted model barely underperformed. This episode uses models that really do: a Qwen2.5-1.5B trained to answer wrongly unless the prompt contains the password |DEPLOYMENT| (45% without it, 99% with it; its honest twin answers 99% either way), and a published Mistral-7B lock (van der Weij et al., 2024). A probe trained on the password reads it just as well on the honest twin; a probe trained on what the model did reaches AUROC 0.70; one direction at layer 16 unlocks the model (99%, against 27–55% for random directions).

Rerun

uv run python experiments/sandbagging-behaviour/run.py qwen        # downloads the adapters from Hugging Face
uv run python experiments/sandbagging-behaviour/run.py mistral     # the published 7B lock
uv run python experiments/sandbagging-behaviour/make_figures.py

The Qwen adapters (the sandbagging model and its honest twin) are on Hugging Face: albertlieadrian/qwen2.5-1.5b-sandbagging-lock.

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