arXiv Machine Learning By Austin Meek, Kyle Cox, Matthew Nguyen, Austin J. Brockmeier, Steven Basart

Mitigating Reward Hacking in Realistic Scenarios Through Representation Engineering

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The paper addresses reward hacking in production machine learning systems, focusing on realistic scenarios such as tool calls and long contexts. It introduces a dynamic intervention that perturbs model representations to steer outputs, using vectors derived from labeled rollouts, gradient optimization, and anti-reward-hacking model specifications. The authors demonstrate that this approach can significantly reduce reward hacking with minimal impact on model coherence or capability, and that steering vectors from coding environments generalize to other domains.

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