arXiv AI By Seyed Mohammad Asghari, Chris Chute, Vikranth Dwaracherla, Xiuyuan Lu, Mehdi Jafarnia, Victor Minden, Zheng Wen, Benjamin Van Roy

Efficient Exploration at Scale

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The paper presents an online learning algorithm that significantly boosts data efficiency for reinforcement learning from human feedback (RLHF). It incrementally updates reward and language models as choice data arrives, using a small affirmative nudge, an epistemic neural network for reward uncertainty, and information‑directed exploration. With Gemma LLMs, the method matches offline RLHF trained on 200K labels using fewer than 20K labels, achieving over a 10× improvement in data efficiency, and projects a 1,000× gain when scaled to 1M labels.

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