Disentangling the Effects of Unlearning in Measuring Parametric Faithfulness of Chain-of-Thought
Ryo Mitsuhashi, Gaku Morio Hitotsubashi University and Hitachi, ltd., Ayana Niwa Mohamed bin Zayed University of Artificial Intelligence, Masahiro Kaneko NII LLMC and Mohamed bin Zayed University of Artificial Intelligence, Kentaro Inui MBZUAI, RIKEN and Tohoku University, Terufumi Morishita Hitachi, ltd, Yuta Koreeda Hitachi, Ltd., Yasuhiro Sogawa Hitachi, Ltd.
原文摘要
Chain-of-Thought (CoT) in large language models (LLMs) has been widely debated in terms of whether it faithfully reflects an internal reasoning process of models. Parametric faithfulness is a recently proposed metric that uses unlearning to assess whether a model encodes parametric beliefs corresponding to a reasoning chain. This paper refines this metric by accounting for the unintended artifacts of unlearning. We introduce control tasks that unlearn irrelevant knowledge and word-shuffled content and show that these control tasks yield substantial parametric faithfulness values, suggesting the non-negligible effect of unlearning. We also found that control tasks help explain the significant variations in parametric faithfulness observed across different model sizes and CoT lengths. We conclude that the effects of unlearning need to be considered when measuring parametric faithfulness.
cs.CL
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 4: Student Research Workshop) · 2026 · 正式发表