arXiv Computation and Language By Juan Terven, Diana-Margarita C\'ordova-Esparza, Ruben Gomez, Carlos Miranda Rocha, Julio-Alejandro Romero-Gonz\'alez, Edgar Chavez-Urbiola

Can Language Models Learn When to Abstain? Policy Learning and Calibrated Answer Selection

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The paper investigates whether language models can learn to abstain from answering when uncertain, focusing on Qwen3-14B for factual questions. Two approaches are examined: training the model itself and training a separate answer selector. The learned selector improves utility over the model’s calibrated confidence filter on TriviaQA, raising coverage from 20.2% to 30.9% and reducing error rate from 23.0% to 14.5%, though gains are inconsistent across datasets and reinforcement‑learning changes do not consistently help.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv Computation and Language.

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