Robust functional PCA for relative data

Jeremy Oguamalam; Peter Filzmoser; Karel Hron; Alessandra Menafoglio; Una Radojičić

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arXiv · 2412.19004

Robust functional PCA for relative data

Jeremy Oguamalam·Peter Filzmoser·Karel Hron·Alessandra Menafoglio·Una Radojičić

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Abstract

This paper introduces a robust approach to functional principal component analysis (FPCA) for relative data, particularly density functions. While recent papers have studied density data within the Bayes space framework, there has been limited focus on developing robust methods to effectively handle anomalous observations and large noise. To address this, we extend the Mahalanobis distance concept to Bayes spaces, proposing its regularized version that accounts for the constraints inherent in density data. Based on this extension, we introduce a new method, robust density principal component analysis (RDPCA), for more accurate estimation of functional principal components in the presence of outliers. The method's performance is validated through simulations and real-world applications, showing its ability to improve covariance estimation and principal component analysis compared to traditional methods.

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BibTeX RIS

Jeremy Oguamalam, Peter Filzmoser, Karel Hron, Alessandra Menafoglio, Una Radojičić. 2024-12-26. Robust functional PCA for relative data. https://arxiv.org/abs/2412.19004

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