Boosting RAG Efficiency With dyRAG: Dynamic Candidate Selection for Optimal Retrieval

Abstract

Retrieval-Augmented Generation (RAG) enhances language model responses by incorporating external knowledge. However, its effectiveness heavily depends on the quality of the retrieved documents. Using a fixed number of retrieved documents $K$ often fails to adapt to varying query complexity, leading either to irrelevant retrievals or to missing crucial evidence. To address this issue, we propose DyRAG, a hybrid retrieval framework that dynamically adjusts $K$ based on query characteristics while maintaining computational efficiency. Our method improves retrieval performance by maximizing relevant information and minimizing noise. We evaluate DyRAG across recommendation, question answering, and fact-checking tasks, where it consistently outperforms fixed- $K$ and hybrid baselines. Compared to traditional approaches, DyRAG demonstrates greater robustness and adaptability across diverse domains.