Contrastive Explainable Clustering with Differential Privacy

DungXXX Nguyen (Department of Computer Science, and Biocomplexity Institute, University of Virginia), Ariel Vetzler (Department of Computer Science, Bar-Ilan University), Sarit Kraus (Department of Computer Science, Bar-Ilan University), Anil Vullikanti (Department of Computer Science, and Biocomplexity Institute, University of Virginia)

Abstract

This paper presents a novel approach to Explainable AI (XAI) that combines contrastive explanations with differential privacy for clustering algorithms. Focusing on k-median and k-means problems, we calculate contrastive explanations as the utility difference between original clustering and clustering with a centroid fixed to a specific data point. This method provides personalized insights into centroid placement. Our key contribution is demonstrating that these differentially private explanations achieve essentially the same utility bounds as non-private explanations. Experiments across various datasets show that our approach offers meaningful, privacy-preserving, and individually relevant explanations without significantly compromising clustering utility. This work advances privacy-aware machine learning by balancing data protection, explanation quality, and personalization in clustering tasks.