论文标题
基于碎屑的多元时间序列的反事实解释
Shapelet-Based Counterfactual Explanations for Multivariate Time Series
论文作者
论文摘要
随着机器学习和深度学习模型在许多领域中变得非常普遍,他们在决策过程中采用的主要保留是它们的黑盒本质。可解释的人工智能(XAI)范式由于其能够降低模型不透明度的能力而获得了很多动力。 XAI方法不仅增加了利益相关者对决策过程的信任,而且还帮助开发商确保了其公平性。最近的努力用于创建透明的模型和事后解释。但是,对于时间序列数据,开发了更少的方法,而在多元数据集方面甚至更少。在这项工作中,我们利用塑形组的固有解释性来开发模型不可知的多元时间序列(MTS)反事实解释算法。反事实可以通过指示在输入上必须执行哪些更改以改变最终决策,从而对制作可解释的黑框模型产生巨大影响。我们在现实生活中的太阳耀斑预测数据集上测试了我们的方法,并证明我们的方法会产生高质量的反事实。此外,与唯一的MTS反事实生成算法的比较表明,除了视觉上可解释外,我们的解释在接近性,稀疏性和合理性方面也很出色。
As machine learning and deep learning models have become highly prevalent in a multitude of domains, the main reservation in their adoption for decision-making processes is their black-box nature. The Explainable Artificial Intelligence (XAI) paradigm has gained a lot of momentum lately due to its ability to reduce models opacity. XAI methods have not only increased stakeholders' trust in the decision process but also helped developers ensure its fairness. Recent efforts have been invested in creating transparent models and post-hoc explanations. However, fewer methods have been developed for time series data, and even less when it comes to multivariate datasets. In this work, we take advantage of the inherent interpretability of shapelets to develop a model agnostic multivariate time series (MTS) counterfactual explanation algorithm. Counterfactuals can have a tremendous impact on making black-box models explainable by indicating what changes have to be performed on the input to change the final decision. We test our approach on a real-life solar flare prediction dataset and prove that our approach produces high-quality counterfactuals. Moreover, a comparison to the only MTS counterfactual generation algorithm shows that, in addition to being visually interpretable, our explanations are superior in terms of proximity, sparsity, and plausibility.