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arXiv · 2502.16797

Forecasting Rare Language Model Behaviors

Erik Jones·Meg Tong·Jesse Mu·Mohammed Mahfoud·Jan Leike·Roger Grosse·Jared Kaplan·William Fithian·Ethan Perez·Mrinank Sharma
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Abstract

Standard language model evaluations can fail to capture risks that emerge only at deployment scale. For example, a model may produce safe responses during a small-scale beta test, yet reveal dangerous information when processing billions of requests at deployment. To remedy this, we introduce a method to forecast potential risks across orders of magnitude more queries than we test during evaluation. We make forecasts by studying each query's elicitation probability -- the probability the query produces a target behavior -- and demonstrate that the largest observed elicitation probabilities predictably scale with the number of queries. We find that our forecasts can predict the emergence of diverse undesirable behaviors -- such as assisting users with dangerous chemical synthesis or taking power-seeking actions -- across up to three orders of magnitude of query volume. Our work enables model developers to proactively anticipate and patch rare failures before they manifest during large-scale deployments.

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Erik Jones, Meg Tong, Jesse Mu, Mohammed Mahfoud, Jan Leike, Roger Grosse, Jared Kaplan, William Fithian, Ethan Perez, Mrinank Sharma. 2025-02-24. Forecasting Rare Language Model Behaviors. https://arxiv.org/abs/2502.16797

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