arXiv AI By Minju Gwak, Alan Ritter

Self-Improvement with Auxiliary Rewards: Learning from Verified Traces and Evaluating Transfer

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The paper investigates whether auxiliary trajectory preferences can enhance small-language-model self‑improvement and transfer when only limited supervision is available. Two reward schemes—confidence‑based (SC) and entropy‑based (UID‑Conj.)—are compared through online reward augmentation and offline training on AIME problems. UID‑Conj. yields a 2.08‑point macro‑average improvement on the adaptation benchmark and outperforms uniform weighting in offline weighted SFT by 1.93 points, with task‑dependent benefits for SC and UID‑Conj. rewards.

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