Weight-Informed Self-Explaining Clustering for Mixed-Type Tabular Data

TL;DR

WISE is a novel unsupervised framework for clustering mixed-type tabular data that unifies representation, feature weighting, clustering, and interpretation, providing high-quality, interpretable results.

Contribution

The paper introduces WISE, a comprehensive unsupervised clustering method with a new encoding, feature weighting, and explanation approach for mixed-type data.

Findings

WISE outperforms classical and neural baselines in clustering quality.

WISE provides faithful, human-interpretable explanations.

The method is efficient on real-world datasets.

Abstract

Clustering mixed-type tabular data is fundamental for exploratory analysis, yet remains challenging due to misaligned numerical-categorical representations, uneven and context-dependent feature relevance, and disconnected and post-hoc explanation from the clustering process. We propose WISE, a Weight-Informed Self-Explaining framework that unifies representation, feature weighting, clustering, and interpretation in a fully unsupervised and transparent pipeline. WISE introduces Binary Encoding with Padding (BEP) to align heterogeneous features in a unified sparse space, a Leave-One-Feature-Out (LOFO) strategy to sense multiple high-quality and diverse feature-weighting views, and a two-stage weight-aware clustering procedure to aggregate alternative semantic partitions. To ensure intrinsic interpretability, we further develop Discriminative FreqItems (DFI), which yields feature-level explanations that are consistent from instances to clusters with an additive decomposition guarantee. Extensive experiments on six real-world datasets demonstrate that WISE consistently outperforms classical and neural baselines in clustering quality while remaining efficient, and produces faithful, human-interpretable explanations grounded in the same primitives that drive clustering.