arXiv Machine Learning By Hyojung Han, Jongmin Kim, Seung-Hun Jeon

Quantize by Drift: Label-Free Mixed-Precision Post-Training Quantization for Text Embedders

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The paper introduces a label‑free mixed‑precision post‑training quantization technique for text embedders called Quantize by Drift. It uses quantization‑induced representation drift—measured by re‑encoding a corpus after quantizing a module—to estimate module sensitivity without relevance labels. Across five development embedders, drift‑based ordering of mixed‑precision plans correlates strongly with held‑out retrieval quality (macro Spearman 0.911) and outperforms uniform precision under a hard byte budget, though it does not fully replace fine‑grained redistribution strategies.

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