arXiv Computation and Language By Junning Shao, Siwei Wang, Zhixuan Fang

Layer-Informed Fine-Tuning via Three-Stage Functional Segmentation of LLMs

Read the original on arXiv Computation and Language →

The paper proposes Layer-Informed Fine-Tuning (LIFT), a method that identifies and updates only the most functionally critical layers of large language models (LLMs) using a bottleneck identification mechanism based on sensitivity analysis. By focusing on layers that handle conceptualization, reasoning, and textualization, LIFT aims to accelerate training and enhance performance on reasoning tasks. Experiments demonstrate that this selective fine-tuning approach both speeds up the training process and yields significant performance gains.

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