🤖 AI Summary
This study addresses the challenge of accurately predicting the performance gain of Retrieval-Augmented Generation (RAG) over non-RAG approaches in question-answering tasks. To overcome limitations of existing prediction methods, the authors propose a novel supervised post-generation predictor that explicitly models the semantic relationships among the input question, retrieved passages, and the generated answer. The approach integrates multi-dimensional signals from pre-retrieval, post-retrieval, and post-generation stages and is optimized through end-to-end training. Experimental results demonstrate that the proposed method significantly outperforms current prediction strategies across multiple benchmarks, offering a reliable basis for deciding whether to activate RAG in practical systems.
📝 Abstract
We address the task of predicting the gain of using RAG (retrieval augmented generation) for question answering with respect to not using it. We study the performance of a few pre-retrieval and post-retrieval predictors originally devised for ad hoc retrieval. We also study a few post-generation predictors, one of which is novel to this study and posts the best prediction quality. Our results show that the most effective prediction approach is a novel supervised predictor that explicitly models the semantic relationships among the question, retrieved passages, and the generated answer.