arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2012.11782cs.LGstat.ML
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基于混合线性优化的有序反事实解释

Ordered Counterfactual Explanation by Mixed-Integer Linear Optimization

Hokkaido University(北海道大学);Fujitsu Laboratories Ltd.(富士通研究所);Tokyo Institute of Technology(东京工业大学)

Kentaro Kanamori, Takuya Takagi, Ken Kobayashi, Yuichi Ike, Kento Uemura, Hiroki Arimura

摘要:

机器学习模型的事后解释方法已被广泛应用于决策支持。其中一种流行的方法是反事实解释(CE),也被称为可操作的追索权,它为用户提供了改变预测结果的特征的扰动向量。给定扰动向量,用户可以将其解释为用于获得期望的决策结果的“动作”。然而,在实践中,仅示出扰动向量通常不足以使用户执行动作。原因在于,如果特征之间存在不对称的相互作用,例如因果关系,则动作的总成本预计将取决于改变特征的顺序。因此,实际的CE方法需要提供一个适当的顺序改变功能,除了一个扰动矢量。为此,我们提出了一个新的框架,称为有序反事实解释(OrdCE)。我们引入了一个新的目标函数,评估一对的动作和功能交互的基础上的顺序。为了提取最优对,我们提出了一个混合整数线性优化方法与我们的目标函数。在真实数据集上的数值实验表明,我们的OrdCE的有效性相比,无序CE方法。

英文摘要:

Post-hoc explanation methods for machine learning models have been widely used to support decision-making. One of the popular methods is Counterfactual Explanation (CE), also known as Actionable Recourse, which provides a user with a perturbation vector of features that alters the prediction result. Given a perturbation vector, a user can interpret it as an "action" for obtaining one's desired decision result. In practice, however, showing only a perturbation vector is often insufficient for users to execute the action. The reason is that if there is an asymmetric interaction among features, such as causality, the total cost of the action is expected to depend on the order of changing features. Therefore, practical CE methods are required to provide an appropriate order of changing features in addition to a perturbation vector. For this purpose, we propose a new framework called Ordered Counterfactual Explanation (OrdCE). We introduce a new objective function that evaluates a pair of an action and an order based on feature interaction. To extract an optimal pair, we propose a mixed-integer linear optimization approach with our objective function. Numerical experiments on real datasets demonstrated the effectiveness of our OrdCE in comparison with unordered CE methods.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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