arXiv AI By Mads Toftrup, Marco Federici, Boris van Breugel, Paul Whatmough, Markus Nagel

A Unified Hessian-Guided Framework for Post-Training Quantization

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The paper introduces a unified Hessian-guided framework for post‑training quantization of large language models. By deriving a Hessian‑based approximation of output changes, it jointly optimizes quantization ranges, linear transformations, and weight rounding under a single output‑sensitivity objective. The method remains practical for modern models and consistently outperforms existing transformation and rounding techniques in both channel‑wise and block‑wise settings.

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