Conference Paper
Large Language Models

Enhancing RAG

Siran Li, Linus Stenzel, Carsten Eickhoff, Seyed Ali Bahrainian
January 13, 2025International Conference on Computational Linguistics56 citations

56

Citations

2

Influential Citations

International Conference on Computational Linguistics

Venue

2025

Year

Abstract

Retrieval-Augmented Generation (RAG) systems have recently shown remarkable advancements by integrating retrieval mechanisms into language models, enhancing their ability to produce more accurate and contextually relevant responses. However, the influence of various components and configurations within RAG systems remains underexplored. A comprehensive understanding of these elements is essential for tailoring RAG systems to complex retrieval tasks and ensuring optimal performance across diverse applications. In this paper, we develop several advanced RAG system designs that incorporate query expansion, various novel retrieval strategies, and a novel Contrastive In-Context Learning RAG. Our study systematically investigates key factors, including language model size, prompt design, document chunk size, knowledge base size, retrieval stride, query expansion techniques, Contrastive In-Context Learning knowledge bases, multilingual knowledge bases, and Focus Mode retrieving relevant context at sentence-level. Through extensive experimentation, we provide a detailed analysis of how these factors influence response quality. Our findings offer actionable insights for developing RAG systems, striking a balance between contextual richness and retrieval-generation efficiency, thereby paving the way for more adaptable and high-performing RAG frameworks in diverse real-world scenarios. Our code and implementation details are publicly available.

Analysis

Why This Paper Matters

Retrieval-Augmented Generation (RAG) has become a cornerstone for enhancing large language models with external knowledge, yet the field has largely relied on ad-hoc configurations. This paper addresses a critical gap by systematically dissecting the components that influence RAG performance. As RAG systems are deployed across diverse real-world scenarios, understanding how factors like chunk size, retrieval stride, and prompt design interact is essential for building efficient and accurate systems. The authors' comprehensive investigation provides a much-needed empirical foundation, moving beyond anecdotal evidence to actionable design principles.

Moreover, the introduction of Contrastive In-Context Learning and Focus Mode (sentence-level retrieval) represents a step toward more nuanced retrieval and generation. By exploring multilingual knowledge bases, the paper also acknowledges the global nature of AI applications. This work is particularly timely as the community seeks to optimize RAG for complex tasks, and its public release of code encourages reproducibility and further innovation.

Technical Contributions

  • Advanced RAG Designs: Introduces multiple system variants that incorporate query expansion and novel retrieval strategies, pushing beyond standard dense or sparse retrieval.
  • Contrastive In-Context Learning RAG: A novel approach that leverages contrastive examples to improve in-context learning, potentially enhancing response relevance and accuracy.
  • Focus Mode: A sentence-level retrieval mechanism that aims to retrieve more precise context, reducing noise from larger document chunks.
  • Systematic Factor Analysis: Investigates a wide range of factors including model size, prompt design, chunk size, knowledge base size, retrieval stride, query expansion, multilingual knowledge bases, and contrastive learning setups.
  • Public Implementation: Releases code and details to facilitate replication and further research.

Results

The abstract does not provide specific numerical metrics, but the study's extensive experimentation yields a detailed analysis of how each factor influences response quality. The authors identify trade-offs between contextual richness and retrieval-generation efficiency, suggesting that optimal configurations depend on the task and resource constraints. For instance, larger knowledge bases may improve coverage but increase latency, while sentence-level retrieval (Focus Mode) may boost precision at the cost of recall. The findings likely include comparisons across model sizes and prompt designs, offering practical guidance for practitioners.

Significance

This paper contributes a systematic framework for understanding RAG systems, which is crucial as they become integral to AI applications. By highlighting the interplay between retrieval and generation, it encourages a more principled approach to system design. The introduction of contrastive in-context learning and sentence-level retrieval opens new avenues for improving RAG performance, particularly in multilingual and knowledge-intensive settings. The public availability of code will accelerate adoption and inspire further research, ultimately leading to more adaptable and efficient RAG systems in real-world deployments.