π€ AI Summary
Existing deep subspace clustering (DSC) methods rely on the strict union-of-subspaces (UoS) assumption and suffer from feature collapse during joint representation and self-expression coefficient learning, lacking theoretical guarantees. This paper proposes PRO-DSCβthe first end-to-end DSC framework that simultaneously provides rigorous theoretical guarantees and structured modeling. Its core contribution is the first theoretical proof that regularized self-expression models prevent feature collapse and ensure that optimal representations exactly lie in an orthogonal UoS. PRO-DSC integrates structured representation regularization, differentiable self-expression modeling, and an efficient optimization algorithm. Extensive experiments on multiple benchmark datasets demonstrate significant improvements over state-of-the-art methods. Empirical results consistently validate the theoretical claims, confirming both the efficacy and soundness of the proposed framework. The implementation is publicly available.
π Abstract
Subspace clustering is a classical unsupervised learning task, built on a basic assumption that high-dimensional data can be approximated by a union of subspaces (UoS). Nevertheless, the real-world data are often deviating from the UoS assumption. To address this challenge, state-of-the-art deep subspace clustering algorithms attempt to jointly learn UoS representations and self-expressive coefficients. However, the general framework of the existing algorithms suffers from a catastrophic feature collapse and lacks a theoretical guarantee to learn desired UoS representation. In this paper, we present a Principled fRamewOrk for Deep Subspace Clustering (PRO-DSC), which is designed to learn structured representations and self-expressive coefficients in a unified manner. Specifically, in PRO-DSC, we incorporate an effective regularization on the learned representations into the self-expressive model, prove that the regularized self-expressive model is able to prevent feature space collapse, and demonstrate that the learned optimal representations under certain condition lie on a union of orthogonal subspaces. Moreover, we provide a scalable and efficient approach to implement our PRO-DSC and conduct extensive experiments to verify our theoretical findings and demonstrate the superior performance of our proposed deep subspace clustering approach. The code is available at https://github.com/mengxianghan123/PRO-DSC.