Source-linked AI summary
SAIL: Search-Augmented Instruction Learning
Hongyin Luo, Yung-Sung Chuang, Yuan Gong, Tianhua Zhang, Yoon Kim, Xixin Wu, Danny Fox, Helen Meng, James Glass
TL;DR
LLMs struggle with stale knowledge, opaque outputs, and distracting search results. SAIL trains LLaMA-7B on search-grounded instruction examples with explicit retrieval selection, and SAIL-7B shows strong instruction following while improving performance and transparency on evaluated tasks.
Problem
LLMs lack up-to-date knowledge and transparent grounding, while search engines can introduce distracting information.
Source: §1 · pp. 1–2Method
SAIL constructs search-grounded instruction examples from multiple retrieval sources and fine-tunes LLaMA-7B to select trustworthy information and generate responses.
Source: §1 · p. 2, §2.1 · p. 3Results
SAIL-7B outperforms strong baseline models on several NLP tasks and improves performance and transparency on instruction-following, question-answering, and fact-checking evaluations.
Source: §1 · p. 2, §5 · pp. 9–10Takeaways & Limitations
Search-augmented instruction learning can help language models distill useful information from noisy search results while producing high-quality responses.
Source: §5 · pp. 9–10SAIL does not explain why a search result is trustworthy or informative.
Source: Limitations · p. 10
Abstract
from arXiv · showhide
Large language models (LLMs) have been significantly improved by instruction fine-tuning, but still lack transparency and the ability to utilize up-to-date knowledge and information. In this work, we propose search-augmented instruction learning (SAIL), which grounds the language generation and instruction following abilities on complex search results generated by in-house and external search engines. With an instruction tuning corpus, we collect search results for each training case from different search APIs and domains, and construct a new search-grounded training set containing \textit{(instruction, grounding information, response)} triplets. We then fine-tune the LLaMA-7B model on the constructed training set. Since the collected results contain unrelated and disputing languages, the model needs to learn to ground on trustworthy search results, filter out distracting passages, and generate the target response. The search result-denoising process entails explicit trustworthy information selection and multi-hop reasoning, since the retrieved passages might be informative but not contain the instruction-following answer. Experiments show that the fine-tuned SAIL-7B model has a strong instruction-following ability, and it performs significantly better on transparency-sensitive tasks, including open-ended question answering and fact checking.
1 Introduction
LLMs offer strong instruction following but remain limited by stale knowledge, opaque generations, and distracting search results. SAIL addresses these problems by training a 7B model to denoise search results and produce grounded responses.
- LLMs may lack up-to-date knowledge because their fixed training data cannot incorporate later information without costly retraining.Source: §1 · p. 1
- LLM generations are opaque and can produce misinformation, stereotypes, or toxic language without trustworthy sources.Source: §1 · p. 1
- Commercial search engines provide current information but can return noisy or distracting passages that mislead language models.Source: §1 · pp. 1–2
- SAIL trains a model to generate responses from noisy search results while learning to denoise retrieval and ground on useful information.Source: §1 · p. 2
- The work constructs a search-augmented instruction corpus and fine-tunes SAIL-7B, which outperforms GPT-3.5-Turbo and Vicuna-13B on several NLP tasks.Source: §1 · p. 2
- Across instruction following, question answering, and language checking, SAIL-7B is robust to distracting retrieval and reaches performance comparable to state-of-the-art instruction-following models.Source: §1 · pp. 2–3
2 Method
SAIL collects heterogeneous search results, labels passages as informative or distracting, and fine-tunes LLaMA-7B to select useful evidence and generate responses. It evaluates instruction following, question answering, and fact or fairness checking under zero-shot and search-augmented settings.
2.1 Search Result Collection
- Queries combine each instruction with its input, and DuckDuckGo plus BM25 Wikipedia retrieval supply retained search-result titles and previews.Source: §2.1 · p. 3
- Training examples pool five retrieved passages and randomly sample zero to three results, exposing the model to varied retrieval sources and quantities.Source: §2.1 · p. 3
2.2 In-context Retrieval Selection
- An entailment model labels a passage informative when its entailment score exceeds its contradiction score; otherwise it is labeled distracting.Source: §2.2 · p. 3
2.3 Fine-tuning
- Prompts place the most relevant retrieval nearest the instruction, and both retrieval-selection sequences and annotated responses are used for fine-tuning.Source: §2.3 · p. 3
2.4 Evaluation
- Instruction-following evaluation compares model responses with GPT-4 using scores on 80 Vicuna-Instructions questions, normalized by GPT-4 scores.Source: §2.4 · pp. 3–4
- Question answering uses CSQA, OBQA, and ARC-Challenge in instructed zero-shot and search-augmentation settings to test sensitivity to noisy retrieval.Source: §2.4 · p. 4
- Fact and fairness checking uses UniLC tasks in zero-shot and search-augmented settings, comparing Vicuna-7B, Vicuna-13B, and SAIL-7B with and without search.Source: §2.4 · p. 4
3 Experiments
Across instruction following, question answering, and fact and fairness checking, SAIL benefits from search augmentation more consistently than baseline models. The results indicate that search-grounded fine-tuning helps models use useful information while resisting distracting retrieval results.
3.1 Instruction Following
- Search-augmented SAIL-7B scores 90% versus below 85% for other models on instruction following, while using fewer training instructions and parameters.It achieves 103% of ChatGPT performance with search and 98% without search, although GPT-4 remains better.Source: §3.1 · p. 4
- Search augmentation improves SAIL-7B from 84% to 90% and from 98% to 103% across the two instruction-following evaluations, whereas it can hurt Vicuna and LLaMA-GPT4 models.The search results contain useful information, but models without search-augmented fine-tuning can be misled by distracting retrieval results.Source: §3.1 · p. 5
3.2 Question Answering
- DuckDuckGo produces better question-answering performance than Wikipedia retrieval across models and tasks, but searched-augmented LLaMA-7B and Vicuna-7B average below 50% accuracy.DuckDuckGo covers a wider range of information, while its results can still include unrelated or distracting passages.Source: §3.2 · p. 7
- Vicuna-13B achieves 51.0% average accuracy without grounding, but search results hurt its accuracy in most experiments, including a 1.4% decrease on ARC-Challenge.Wikipedia BM25 results decrease its accuracy by as much as 1.8%, showing that a larger baseline does not reliably exploit retrieved evidence.Source: §3.2 · p. 7
- SAIL-7B improves on all three question-answering tasks with search results and reaches 1.2% higher average accuracy, including gains of 2.8% on OBQA.Without retrieval, SAIL-7B averages 49.5%, versus 44.5% for LLaMA-7B and 40.9% for Vicuna-7B; search-augmented SAIL-7B performs best on CSQA and OBQA.Source: §3.2 · pp. 7–8
3.3 Fact and Fairness Checking
- SAIL-7B achieves the highest accuracy and F1 scores on all four UniLC fact and fairness tasks without grounding, while search augmentation improves its fact-checking results on both evaluated tasks.On Climate-Fever, the improvement reaches 4.2%, and augmented SAIL outperforms baselines by 9% accuracy and 5% F1.Source: §3.3 · p. 8
4 Related Work
Prior work developed instruction-tuned and retrieval-augmented language models, while SAIL combines real-world search, explicit denoising, and instruction fine-tuning to broaden their applications.
4.1 Capabilities
- Large language models exhibit zero-shot multitask solving and few-shot in-context learning with chain-of-thought reasoning.These capabilities provide the broader language-model context for instruction following and retrieval augmentation.Source: §4.1 · p. 8
- Instruction tuning improves zero-shot task performance and enables models such as InstructGPT, ChatGPT, and GPT-4 to handle diverse tasks without demonstrations.Research also explores generated instructions and instruction-following outputs to improve this capability.Source: §4.1 · pp. 8–9
- Retrieval-augmented language models have used end-to-end retriever training, frozen retrievers, dedicated losses, or frozen language models with tuned retrieval modules.Examples include REALM, RAG, RETRO, Atlas, RePlug, and In-context RALM.Source: §4.1 · p. 9
- SAIL addresses prior retrieval-augmented models’ closed-corpus, distraction, and limited instruction-tuning constraints by using real-world search engines, search-result denoising, and instruction fine-tuning.These changes support broader applications including chatbot instruction following, fact checking, and fairness checking.Source: §4.1 · p. 9
4.2 Trustworthiness
- Self-improvement methods use chain-of-thought, self-consistency, in-context examples, self-reflection, and self-refinement to improve reasoning or adaptation.These approaches concern model-generated reasoning and refinement rather than SAIL’s search-result denoising process.Source: §4.2 · p. 9
- Fact and fairness checking research examines whether language models can identify hallucinations and assess harmful language produced by humans or machines.This motivates trustworthiness-oriented evaluation alongside response generation.Source: §4.2 · p. 9
5 Conclusion
SAIL constructs a search-augmented instruction-tuning corpus and fine-tunes a 7B-parameter model to distill trustworthy information from disputed and distracting search results. Experiments show improved performance and transparency across instruction following, question answering, and fact and fairness checking.
5 Conclusion
- The paper constructs a search-augmented instruction-tuning corpus combining human instructions, GPT-4 responses, and BM25 and commercial-search results, then fine-tunes LLaMA-7B.The corpus is designed to address disputed and distracting retrieval results during generation.Source: §5 · p. 9
- SAIL-7B distills trustworthy and helpful information from search results and generates high-quality responses across instruction following, question answering, and fact/fairness checking.The reported outcome is improvement in both performance and transparency for instruction-following language models.Source: §5 · pp. 9–10
Limitations
SAIL achieves high performance with efficient model settings, but it does not explain why retrieved search results are trustworthy or informative.
Limitations
- SAIL’s major limitation is that it does not explain why a search result is trustworthy or informative.Future work proposes larger models that recognize trustworthy search results with explanations.Source: Limitations · p. 10