Unsupervised feature selection via low-rank graph embedding

Document Type : Research Paper

Author

Department of Electrical Engineering, Lorestan University, Khoramabad, Iran

Abstract

In unsupervised feature selection, the absence of class labels makes it necessary to rely on statistical measures like variance to assess feature importance. However, the presence of noise, outliers, and feature redundancy can significantly reduce the accuracy of this process, negatively affecting the performance of machine learning models. To address these issues, this paper proposes the UFSLRAGE algorithm, which begins by applying the LRAGE feature extraction method to minimize reconstruction error, adaptively updating the similarity between samples to remove noise and outliers while generating orthogonal and uncorrelated features. This paper then constructs a weighted bipartite graph that represents both original and extracted features, with cosine similarity determining the edge weights. The LAPJV algorithm is used to identify a maximum matching in this graph, where the vertices corresponding to the original features are selected as the most informative ones. This paper evaluates UFSLRAGE on five widely-used image datasets: Jaffe, Yale, ORL, COIL-20, and pixraw10P, using metrics such as accuracy, normalized mutual information (NMI), precision, recall, and F-measure. Experimental results demonstrate that UFSLRAGE consistently outperforms other state-of-the-art unsupervised feature selection methods, achieving an average NMI of 0.9358 and an average accuracy of 0.9333 on the pixraw10P face image dataset with 10,000 features.

Keywords

Main Subjects


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Articles in Press, Accepted Manuscript
Available Online from 20 April 2026
  • Receive Date: 02 October 2025
  • Revise Date: 19 February 2026
  • Accept Date: 20 April 2026