ExplainabilityTransparencyAccountabilitycs.AI
CAGE: Causality-Aware Shapley Value for Global Explanations
Nils Ole Breuer, Andreas Sauter, Majid Mohammadi, Erman Acar
April 17, 2024
xAI
4 citations
Key Takeaways
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Current explanation methods miss important relationships: Most AI explanation techniques assume features work independently, but in reality, features often influence each other. CAGE addresses this by incorporating causal relationships—how one feature actually causes changes in another—into explanations of which features matter most for AI decisions.
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Causality improves explanation accuracy and trustworthiness: The paper demonstrates that explanations become "more faithful" (better aligned with how the model actually works) when causal relationships are considered. This means users get a more accurate picture of why an AI system made a particular decision, rather than a misleading oversimplification.
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Better explanations support responsible AI deployment: By making feature importance explanations more intuitive and accurate through causal reasoning, CAGE helps stakeholders—including regulators, auditors, and affected individuals—better understand and scrutinize AI decisions. This transparency is essential for identifying potential biases or errors before AI systems are deployed in high-stakes domains like healthcare or criminal justice.
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The method works on real-world problems: The researchers validated CAGE on both synthetic test data and real-world datasets, suggesting the approach is practical and applicable beyond theoretical exercises, making it potentially useful for explaining actual AI systems in production.
Abstract
As Artificial Intelligence (AI) is having more influence on our everyday lives, it becomes important that AI-based decisions are transparent and explainable. As a consequence, the field of eXplainable AI (or XAI) has become popular in recent years. One way to explain AI models is to elucidate the predictive importance of the input features for the AI model in general, also referred to as global explanations. Inspired by cooperative game theory, Shapley values offer a convenient way for quantifying the feature importance as explanations. However many methods based on Shapley values are built on the assumption of feature independence and often overlook causal relations of the features which could impact their importance for the ML model. Inspired by studies of explanations at the local level, we propose CAGE (Causally-Aware Shapley Values for Global Explanations). In particular, we introduce a novel sampling procedure for out-coalition features that respects the causal relations of the input features. We derive a practical approach that incorporates causal knowledge into global explanation and offers the possibility to interpret the predictive feature importance considering their causal relation. We evaluate our method on synthetic data and real-world data. The explanations from our approach suggest that they are not only more intuitive but also more faithful compared to previous global explanation methods.
Paper Info
arXiv ID2404.11208
PublishedApril 17, 2024
Citations
4
Relevance82%
VenuexAI
TypeJournalArticle
Categorycs.AI
Responsible AI Topics
Explainability