Angular Embedding: A New Angular Robust Principal Component Analysis

Shenglan Liu; Yang Yu

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arXiv · 2011.11013

Angular Embedding: A New Angular Robust Principal Component Analysis

Shenglan Liu·Yang Yu

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Abstract

As a widely used method in machine learning, principal component analysis (PCA) shows excellent properties for dimensionality reduction. It is a serious problem that PCA is sensitive to outliers, which has been improved by numerous Robust PCA (RPCA) versions. However, the existing state-of-the-art RPCA approaches cannot easily remove or tolerate outliers by a non-iterative manner. To tackle this issue, this paper proposes Angular Embedding (AE) to formulate a straightforward RPCA approach based on angular density, which is improved for large scale or high-dimensional data. Furthermore, a trimmed AE (TAE) is introduced to deal with data with large scale outliers. Extensive experiments on both synthetic and real-world datasets with vector-level or pixel-level outliers demonstrate that the proposed AE/TAE outperforms the state-of-the-art RPCA based methods.

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BibTeX RIS

Shenglan Liu, Yang Yu. 2020-11-22. Angular Embedding: A New Angular Robust Principal Component Analysis. https://arxiv.org/abs/2011.11013

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