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arXiv · 2604.26483

Efficient Listwise Reranking with Compressed Document Representations

Abstract

Reranking, the process of refining the output from a first-stage retriever, is often considered computationally expensive, especially when using Large Language Models (LLMs). A common approach to mitigate this cost involves utilizing smaller LLMs or controlling input length. Inspired by recent advances in document compression for retrieval-augmented generation (RAG), we introduce RRK, an efficient and effective listwise reranker compressing documents into multi-token fixed-size embedding representations. Our simple training via distillation shows that this combination of rich compressed representations and listwise reranking yields a highly efficient and effective system. In particular, our 8B-parameter model runs 3x-18x faster than smaller rerankers (0.6-4B parameters) while matching or outperforming them in effectiveness. The efficiency gains are even more striking on long-document benchmarks, where RRK widens its advantage further.

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BibTeXRIS

Hervé Déjean, Stéphane Clinchant. 2026-04-29. Efficient Listwise Reranking with Compressed Document Representations. https://arxiv.org/abs/2604.26483

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