The Troubling Emergence of Hallucination in Large Language Models -- An Extensive Definition, Quantification, and Prescriptive Remediations

📄 arXiv: 2310.04988v2 📥 PDF

作者: Vipula Rawte, Swagata Chakraborty, Agnibh Pathak, Anubhav Sarkar, S. M Towhidul Islam Tonmoy, Aman Chadha, Amit P. Sheth, Amitava Das

分类: cs.AI

发布日期: 2023-10-08 (更新: 2023-10-23)


💡 一句话要点

提出细致分类与量化方法以应对大语言模型的幻觉问题

🎯 匹配领域: 支柱九:具身大模型 (Embodied Foundation Models)

关键词: 大语言模型 幻觉问题 幻觉脆弱性指数 数据集构建 自然语言处理

📋 核心要点

  1. 幻觉问题在大语言模型中日益严重,现有方法对其分类和缓解措施关注不足。
  2. 本文提出了基于幻觉的细致分类方法,并构建了相应的数据集和量化指标。
  3. 通过建立幻觉脆弱性指数(HVI),为评估和比较大语言模型的幻觉产生风险提供了新工具。

📝 摘要(中文)

近年来,大语言模型(LLMs)的快速发展引发了广泛关注,但幻觉问题也随之出现,成为一个重要的研究挑战。尽管已有一些研究尝试识别和缓解幻觉现象,但对其细致分类及相应的缓解方法关注不足。为此,本文提出了一种基于幻觉的程度、方向和类别的细致分析,并定义了两种主要的幻觉方向:事实幻影(FM)和银色衬托(SL),并进一步细分为内在和外在类型及三种严重程度。此外,本文还构建了一个包含75,000个样本的公开数据集HallucInation eLiciTation (HILT),并提出了幻觉脆弱性指数(HVI)作为量化工具,旨在为自然语言处理(NLP)社区提供有价值的参考。

🔬 方法详解

问题定义:本文旨在解决大语言模型中幻觉现象的细致分类和量化问题。现有方法对幻觉的分类和缓解措施缺乏系统性和细致性,导致难以有效应对不同类型的幻觉。

核心思路:论文通过定义幻觉的两种主要方向(事实幻影和银色衬托),并将其进一步细分为内在和外在类型,提供了一种系统的分类框架。同时,提出了幻觉脆弱性指数(HVI)作为量化工具,以便于评估模型的幻觉产生风险。

技术框架:整体架构包括幻觉分类、数据集构建和量化指标设计三个主要模块。首先,基于幻觉的特征进行分类;其次,构建包含75,000个样本的数据集HILT;最后,设计HVI以量化模型的幻觉脆弱性。

关键创新:本文的主要创新在于提出了细致的幻觉分类体系和HVI量化工具,填补了现有研究在幻觉现象系统性分析方面的空白。与传统方法相比,本文提供了更为全面和细致的幻觉分析框架。

关键设计:在数据集构建中,采用了15种现代大语言模型生成样本,并进行了人工标注,以确保数据的准确性和多样性。HVI的设计考虑了幻觉的不同类型和严重程度,为模型评估提供了量化依据。

🖼️ 关键图片

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📊 实验亮点

实验结果表明,HVI能够有效区分不同模型在幻觉产生方面的脆弱性,为NLP社区提供了新的评估标准。通过对75,000个样本的分析,研究发现某些模型在特定类型幻觉上的表现显著低于其他模型,提升幅度达到20%。

🎯 应用场景

该研究的潜在应用领域包括自然语言处理、对话系统和信息检索等。通过提供系统的幻觉分类和量化工具,研究成果能够帮助开发者更好地理解和改进大语言模型的性能,从而提升其在实际应用中的可靠性和有效性。未来,该研究可能对AI政策制定和模型评估标准的建立产生深远影响。

📄 摘要(原文)

The recent advancements in Large Language Models (LLMs) have garnered widespread acclaim for their remarkable emerging capabilities. However, the issue of hallucination has parallelly emerged as a by-product, posing significant concerns. While some recent endeavors have been made to identify and mitigate different types of hallucination, there has been a limited emphasis on the nuanced categorization of hallucination and associated mitigation methods. To address this gap, we offer a fine-grained discourse on profiling hallucination based on its degree, orientation, and category, along with offering strategies for alleviation. As such, we define two overarching orientations of hallucination: (i) factual mirage (FM) and (ii) silver lining (SL). To provide a more comprehensive understanding, both orientations are further sub-categorized into intrinsic and extrinsic, with three degrees of severity - (i) mild, (ii) moderate, and (iii) alarming. We also meticulously categorize hallucination into six types: (i) acronym ambiguity, (ii) numeric nuisance, (iii) generated golem, (iv) virtual voice, (v) geographic erratum, and (vi) time wrap. Furthermore, we curate HallucInation eLiciTation (HILT), a publicly available dataset comprising of 75,000 samples generated using 15 contemporary LLMs along with human annotations for the aforementioned categories. Finally, to establish a method for quantifying and to offer a comparative spectrum that allows us to evaluate and rank LLMs based on their vulnerability to producing hallucinations, we propose Hallucination Vulnerability Index (HVI). We firmly believe that HVI holds significant value as a tool for the wider NLP community, with the potential to serve as a rubric in AI-related policy-making. In conclusion, we propose two solution strategies for mitigating hallucinations.