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arXiv · 2403.01267

Dissecting Language Models: Machine Unlearning via Selective Pruning

Nicholas Pochinkov·Nandi Schoots
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Abstract

Understanding and shaping the behaviour of Large Language Models (LLMs) is increasingly important as applications become more powerful and more frequently adopted. This paper introduces a machine unlearning method specifically designed for LLMs. We introduce a selective pruning method for LLMs that removes neurons based on their relative importance on a targeted capability compared to overall network performance. This approach is a compute- and data-efficient method for identifying and removing neurons that enable specific behaviours. Our findings reveal that both feed-forward and attention neurons in LLMs are specialized; that is, for specific tasks, certain neurons are more crucial than others. Code from all experiments is available at https://github.com/nickypro/selective-pruning

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Nicholas Pochinkov, Nandi Schoots. 2024-03-02. Dissecting Language Models: Machine Unlearning via Selective Pruning. https://arxiv.org/abs/2403.01267

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