arXiv:2505.03201stat.MLcs.LG2025-05

改进视觉模型解释性,让基线图像按重要性加权,提升归因可靠性。

Enhancing Visual Feature Attribution via Weighted Integrated Gradients

  • 基于输入动态加权基线图像,不再假设所有基线同等重要。
  • 在多个模型上比传统方法提升36%的归因质量。
  • 适合需要高可信度解释的视觉AI应用,如医疗影像分析。

集成梯度(IG)是可解释人工智能中广泛使用的归因方法,尤其在计算机视觉中至关重要。其主要缺陷是受基线图像选择的影响。多基线扩展方法如期望梯度(EG)默认对所有基线均匀加权,但在高维视觉模型中常导致噪声大、不稳定的解释。本文提出加权集成梯度(WG),通过无监督准则评估基线适用性,实现对基线的自适应选择与加权。该方法在广义加权基线形式下保持了IG的核心公理性质。在代理拟合-相关性单调性假设下,提供概率依据支持为更信息丰富的基线分配更高权重。在常用图像数据集和模型上的实验表明,相较于原有协议下的EG,WG性能提升最高达36%,覆盖卷积与Transformer架构。该提升伴随额外的适配性评估开销,因此应视为归因保真度与效率的权衡,而非更快替代方案。通过摒弃基线等价假设,WG为视觉模型解释提供了更清晰可靠的新途径,增强了可解释人工智能的理解力与实用性。

原文摘要 · Abstract (English)

Integrated Gradients (IG) is a widely used attribution method in explainable AI, particularly in computer vision applications where reliable feature attribution is essential. A key limitation of IG is its sensitivity to the choice of baseline (reference) images. Multi-baseline extensions such as Expected Gradients (EG) assume uniform weighting over baselines, implicitly treating all baseline images as equally informative. In high-dimensional vision models, this assumption often leads to noisy or unstable explanations. This paper proposes Weighted Integrated Gradients (WG), a principled approach that evaluates and weights baselines to enhance attribution reliability. WG introduces an unsupervised criterion for baseline suitability, enabling adaptive selection and weighting of baselines on a per-input basis. The method preserves the core axiomatic properties of IG in a generalized weighted-baseline form. Under an expected, proxy-based fitness--relevance monotonicity assumption, WG provides a probabilistic justification for assigning larger weights to more informative baselines. Experiments on commonly used image datasets and models show that WG improves over EG under our protocol, with up to 36% gains across evaluated convolutional and Transformer architectures. These gains come with additional fitness-evaluation cost, so WG should be viewed as an attribution-fidelity trade-off rather than a faster alternative to EG. By moving beyond the assumption that all baselines contribute equally, Weighted Integrated Gradients offers a clearer and more reliable approach to explaining computer-vision models, improving both understanding and practical usability in explainable AI.

可解释AI视觉归因深度学习

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。