arXiv AI By Lingfang Li, Procheta Sen, Shubham Das, Danushka Bollegala

Decoupling Internal Representational Changes and Causal Importance in Fine-Tuned Large Language Models

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Fine‑tuning reshapes internal representations of large language models, affecting attention patterns and layer‑wise activations. The study shows that components identified by EAP as important for task performance cluster in specific layers, yet these layers do not align with those undergoing the largest representational changes. Additionally, overlapping EAP components across different tasks do not guarantee cross‑task transfer and can even degrade performance when tasks differ in nature.

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