TaiMing Lu


2024

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Insights into LLM Long-Context Failures: When Transformers Know but Don’t Tell
Muhan Gao | TaiMing Lu | Kuai Yu | Adam Byerly | Daniel Khashabi
Findings of the Association for Computational Linguistics: EMNLP 2024

Large Language Models (LLMs) exhibit positional bias, struggling to utilize information from the middle or end of long contexts. Our study explores LLMs’ long-context reasoning by probing their hidden representations. We find that while LLMs encode the position of target information, they often fail to leverage this in generating accurate responses. This reveals a disconnect between information retrieval and utilization, a “know but don’t tell” phenomenon. We further analyze the relationship between extraction time and final accuracy, offering insights into the underlying mechanics of transformer models.