Neural Approaches to Conversational Information Retrieval
Jianfeng Gao, Chenyan Xiong, Paul Bennett, Nick Craswell
TL;DR
This work surveys neural approaches to conversational information retrieval (CIR), framing CIR as a task-oriented dialogue problem that combines contextual understanding, multi-modal retrieval, and natural language generation. It details architectures, benchmarks, and learning paradigms, including dense and sparse retrieval, QMDS, CMC, and C-KBQA, along with evaluation strategies and proactive conversational techniques. The contributions include a comprehensive taxonomy of CIR components, neural models for end-to-end CIR pipelines, and case studies of commercial systems, highlighting how modern PLMs and neural readers enable human-centric, interactive information access. The findings illustrate the centrality of contextual understanding, task-oriented dialog management, and grounded generation in achieving effective, scalable CIR across open-domain and knowledge-base settings, with strong emphasis on evaluation, safety, and continual learning.
Abstract
A conversational information retrieval (CIR) system is an information retrieval (IR) system with a conversational interface which allows users to interact with the system to seek information via multi-turn conversations of natural language, in spoken or written form. Recent progress in deep learning has brought tremendous improvements in natural language processing (NLP) and conversational AI, leading to a plethora of commercial conversational services that allow naturally spoken and typed interaction, increasing the need for more human-centric interactions in IR. As a result, we have witnessed a resurgent interest in developing modern CIR systems in both research communities and industry. This book surveys recent advances in CIR, focusing on neural approaches that have been developed in the last few years. This book is based on the authors' tutorial at SIGIR'2020 (Gao et al., 2020b), with IR and NLP communities as the primary target audience. However, audiences with other background, such as machine learning and human-computer interaction, will also find it an accessible introduction to CIR. We hope that this book will prove a valuable resource for students, researchers, and software developers. This manuscript is a working draft. Comments are welcome.
