Adversarial Subspace Generation for Outlier Detection in High-Dimensional Data

Jul 2025 · Papers

Transactions on Machine Learning Research (TMLR)

Given a domain $\mathcal X$ that is a union of submanifolds $\lbrace S_i \rbrace_{i=1}^d$, how do you recover each one? We answer this in the axis-parallel case, where $\mathcal X \subseteq \mathbb R^d$ and every $S_i$ is generated by canonical vectors---think lines and planes parallel to the axes.

We first build the theoretical framework: Myopic Subspace Theory (MST) describes probability measures on $\mathcal X = \cup_{i=1}^d S_i$ through their marginals on each submanifold. On top of MST we build V-GAN, the first non-parametric probabilistic method for subspace selection---a generative model that, instead of images or text, generates the maps $\mathcal X \to S_i$. Across 42 real-world datasets, ensembles built on V-GAN subspaces improve one-class classification significantly over the competition.

Cite
@ARTICLE{cribeiro25adversarial,
  AUTHOR =       {Jose Cribeiro-Ramallo and Federico Matteucci and Paul Enciu and Alexander Jenke and Vadim Arzamasov and Thorsten Strufe and Klemens B{\"o}hm},
  TITLE =        {Adversarial Subspace Generation for Outlier Detection in High-Dimensional Data},
  JOURNAL =      {Transactions on Machine Learning Research},
  YEAR =         {2025},
}