In plain words: A small classifier sorts each question by difficulty and picks the right answering strategy: answer from memory, look up one fact, or search repeatedly. On open-domain question answering it improved both accuracy and efficiency over baselines, including ones that already adapt retrieval.
Abstract · Adaptive-RAG: Learning to Adapt Retrieval-Augmented Large Language Models through Question Complexity
Retrieval-Augmented Large Language Models (LLMs), which incorporate the non-parametric knowledge from external knowledge bases into LLMs, have emerged as a promising approach to enhancing response accuracy in several tasks, such as Question-Answering (QA). However, even though there are various approaches dealing with queries of different complexities, they either handle simple queries with unnecessary computational overhead or fail to adequately address complex multi-step queries; yet, not all user requests fall into only one of the simple or complex categories. In this work, we propose a novel adaptive QA framework, that can dynamically select the most suitable strategy for (retrieval-augmented) LLMs from the simplest to the most sophisticated ones based on the query complexity. Also, this selection process is operationalized with a classifier, which is a smaller LM trained to predict the complexity level of incoming queries with automatically collected labels, obtained from actual predicted outcomes of models and inherent inductive biases in datasets. This approach offers a balanced strategy, seamlessly adapting between the iterative and single-step retrieval-augmented LLMs, as well as the no-retrieval methods, in response to a range of query complexities. We validate our model on a set of open-domain QA datasets, covering multiple query complexities, and show that ours enhances the overall efficiency and accuracy of QA systems, compared to relevant baselines including the adaptive retrieval approaches. Code is available at: https://github.com/starsuzi/Adaptive-RAG.
Soyeong Jeong, Jinheon Baek, Sukmin Cho, Sung Ju Hwang, Jong C. Park
arXiv:2403.14403 · cs.CL, cs.AI · submitted Mar 21, 2024 · updated Mar 28, 2024
abstract · pdf · html · NAACL 2024
That being said, it is a bit frustrating that so much RAG research focuses on multi-hop approaches with LLMs. IME multiple round trips to an LLM is essentially a non-starter for any serious consumer product as it's far too slow. Smaller models can struggle to follow instructions so they often can't be an adequate replacement even for simpler tasks. Curious to hear if other folks working in this space have had any success thinking critically about these types of problems!