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Spectropolarimetric inversions of solar observations are fundamental for the estimation of the magnetic field in the solar atmosphere. However, instrumental noise, computational requirements, and varying levels of physical realism make it…

Solar and Stellar Astrophysics · Physics 2025-02-20 Robert Jarolim , Momchil E. Molnar , Benoit Tremblay , Rebecca Centeno , Matthias Rempel

Principal component analysis (PCA) has been widely applied to dimensionality reduction and data pre-processing for different applications in engineering, biology and social science. Classical PCA and its variants seek for linear projections…

Machine Learning · Computer Science 2017-07-11 Xiaojun Chang , Feiping Nie , Yi Yang , Heng Huang

Tracing of the magnetic field with Velocity Gradient Technique (VGT) allows observers to probe magnetic field directions with spectroscopic data. In this paper, we employ the method of Principal Component Analysis (PCA) to extract the…

Astrophysics of Galaxies · Physics 2018-07-25 Yue Hu , Ka Ho Yuen , A. Lazarian

When inverting solar spectra, image degradation effects that are present in the data are usually approximated or not considered. We develop a data reduction method that takes these issues into account and minimizes the resulting errors. By…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 M. van Noort

Principal Component Analysis (PCA) is widely used for dimensionality reduction and data analysis. However, PCA results are adversely affected by outliers often observed in real-world data. Existing robust PCA methods are often…

Computational Engineering, Finance, and Science · Computer Science 2025-06-23 Timbwaoga Aime Judicael Ouermi , Jixian Li , Chris R. Johnson

The research detailed in this paper scrutinizes Principal Component Analysis (PCA), a seminal method employed in statistics and machine learning for the purpose of reducing data dimensionality. Singular Value Decomposition (SVD) is often…

Methodology · Statistics 2024-04-02 Donggun Kim , Kisung You

Singular value decomposition (SVD) based principal component analysis (PCA) breaks down in the high-dimensional and limited sample size regime below a certain critical eigen-SNR that depends on the dimensionality of the system and the…

Statistics Theory · Mathematics 2019-12-17 Arvind Prasadan , Raj Rao Nadakuditi , Debashis Paul

With the development of high-throughput technologies, principal component analysis (PCA) in the high-dimensional regime is of great interest. Most of the existing theoretical and methodological results for high-dimensional PCA are based on…

Statistics Theory · Mathematics 2019-03-11 Rounak Dey , Seunggeun Lee

Principal component analysis (PCA) is one of the most widely used dimensionality reduction tools in data analysis. The PCA direction is a linear combination of all features with nonzero loadings -- this impedes interpretability. Sparse PCA…

Optimization and Control · Mathematics 2021-08-18 Santanu S. Dey , Rahul Mazumder , Guanyi Wang

An empirical method of modeling the stellar spectrum of galaxies is proposed, based on two successive applications of Principal Component Analysis (PCA). PCA is first applied to the newly available stellar library STELIB, supplemented by…

Astrophysics · Physics 2009-11-10 Cheng Li , Ting-Gui Wang , Hong-Yan Zhou , Xiao-Bo Dong , Fu-Zhen Cheng

Principal Component Analysis (PCA) has been used to study the pathogenesis of diseases. To enhance the interpretability of classical PCA, various improved PCA methods have been proposed to date. Among these, a typical method is the…

Machine Learning · Computer Science 2019-05-29 Chun-Mei Feng , Yong Xu , Jin-Xing Liu , Ying-Lian Gao , Chun-Hou Zheng

Stokes inversion techniques are very powerful methods for obtaining information on the thermodynamic and magnetic properties of solar and stellar atmospheres. In recent years, very sophisticated inversion codes have been developed that are…

Solar and Stellar Astrophysics · Physics 2022-03-23 C. J. Díaz Baso , A. Asensio Ramos , J. de la Cruz Rodríguez

Sparse principal component analysis (sPCA) enhances the interpretability of principal components (PCs) by imposing sparsity constraints on loading vectors (LVs). However, when used as a precursor to independent component analysis (ICA) for…

Computer Vision and Pattern Recognition · Computer Science 2024-11-20 Muhammad Usman Khalid

This paper examines several applications of principal component analysis (PCA) to physical systems. The first of these demonstrates that the principal components in a basis of appropriate system variables can be employed to identify…

Data Analysis, Statistics and Probability · Physics 2021-02-24 David Yevick

In the current context of data explosion, online techniques that do not require storing all data in memory are indispensable to routinely perform tasks like principal component analysis (PCA). Recursive algorithms that update the PCA with…

Machine Learning · Statistics 2015-11-13 Hervé Cardot , David Degras

Principle Component Analysis PCA is a classical feature extraction and data representation technique widely used in pattern recognition. It is one of the most successful techniques in face recognition. But it has drawback of high…

Computer Vision and Pattern Recognition · Computer Science 2012-06-26 Manal Abdullah , Majda Wazzan , Sahar Bo-saeed

Indexing is a well-known database technique used to facilitate data access and speed up query processing. Nevertheless, the construction and modification of indexes are very expensive. In traditional approaches, all records in the database…

Databases · Computer Science 2023-06-22 Wojciech Macyna , Michal Kukowski

Principal Component Analysis (PCA) is a popular tool for dimensionality reduction and feature extraction in data analysis. There is a probabilistic version of PCA, known as Probabilistic PCA (PPCA). However, standard PCA and PPCA are not…

Machine Learning · Computer Science 2019-04-16 Bowen Zhao , Xi Xiao , Wanpeng Zhang , Bin Zhang , Shutao Xia

We introduce a new rotationally invariant viewing angle classification method for identifying, among a large number of Cryo-EM projection images, similar views without prior knowledge of the molecule. Our rotationally invariant features are…

Biomolecules · Quantitative Biology 2014-03-19 Zhizhen Zhao , Amit Singer

In recent years, Artificial Intelligence techniques have proved to be very successful when applied to problems in physical sciences. Here we apply an unsupervised Machine Learning (ML) algorithm called Principal Component Analysis (PCA) as…

Materials Science · Physics 2021-05-26 T. Tula , G. Möller , J. Quintanilla , S. R. Giblin , A. D. Hillier , E. E. McCabe , S. Ramos , D. S. Barker , S. Gibson