English
Related papers

Related papers: X-ray spectral variability of blazars using princi…

200 papers

Principal component analysis is an important pattern recognition and dimensionality reduction tool in many applications. Principal components are computed as eigenvectors of a maximum likelihood covariance $\widehat{\Sigma}$ that…

Statistics Theory · Mathematics 2017-10-30 Raphael Hauser , Raul Kangro , Jüri Lember , Heinrich Matzinger

Uncertainty quantification is crucial for the deployment of image restoration models in safety-critical domains, like autonomous driving and biological imaging. To date, methods for uncertainty visualization have mainly focused on per-pixel…

Computer Vision and Pattern Recognition · Computer Science 2023-11-07 Elias Nehme , Omer Yair , Tomer Michaeli

Sparse Principal Component Analysis (PCA) methods are efficient tools to reduce the dimension (or the number of variables) of complex data. Sparse principal components (PCs) are easier to interpret than conventional PCs, because most…

Statistics Theory · Mathematics 2011-04-22 Dan Shen , Haipeng Shen , J. S. Marron

Aims: We show the use of principal component analysis (PCA) and Fourier decomposition (FD) method as tools for variable star diagnostics and compare their relative performance in studying the changes in the light curve structures of…

Solar and Stellar Astrophysics · Physics 2015-05-13 Sukanta Deb , Harinder P. Singh

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

Cryo-electron microscopy nowadays often requires the analysis of hundreds of thousands of 2D images as large as a few hundred pixels in each direction. Here we introduce an algorithm that efficiently and accurately performs principal…

Computer Vision and Pattern Recognition · Computer Science 2015-12-16 Zhizhen Zhao , Yoel Shkolnisky , Amit Singer

When functional data manifest amplitude and phase variations, a commonly-employed framework for analyzing them is to take away the phase variation through a function alignment and then to apply standard tools to the aligned functions. A…

Methodology · Statistics 2017-05-30 Sungwon Lee , Sungkyu Jung

The principal component analysis (PCA) is a staple statistical and unsupervised machine learning technique in finance. The application of PCA in a financial setting is associated with several technical difficulties, such as numerical…

Statistical Finance · Quantitative Finance 2021-08-31 Paul Bilokon , David Finkelstein

Principal component analysis is a powerful statistical system to investigate the structure and dynamics of the molecular interstellar medium, with particular emphasis on the study of turbulence, as revealed by spectroscopic imaging of…

Astrophysics of Galaxies · Physics 2015-06-16 C. M. Brunt , M. H. Heyer

Given a sample covariance matrix, we examine the problem of maximizing the variance explained by a linear combination of the input variables while constraining the number of nonzero coefficients in this combination. This is known as sparse…

Optimization and Control · Mathematics 2010-12-24 Youwei Zhang , Alexandre d'Aspremont , Laurent El Ghaoui

This is a tutorial and survey paper on factor analysis, probabilistic Principal Component Analysis (PCA), variational inference, and Variational Autoencoder (VAE). These methods, which are tightly related, are dimensionality reduction and…

Machine Learning · Statistics 2022-05-25 Benyamin Ghojogh , Ali Ghodsi , Fakhri Karray , Mark Crowley

Regularized variants of Principal Components Analysis, especially Sparse PCA and Functional PCA, are among the most useful tools for the analysis of complex high-dimensional data. Many examples of massive data, have both sparse and…

Machine Learning · Statistics 2019-08-21 Genevera I. Allen , Michael Weylandt

Principal component analysis (PCA) is an indispensable tool in many learning tasks that finds the best linear representation for data. Classically, principal components of a dataset are interpreted as the directions that preserve most of…

Optimization and Control · Mathematics 2018-03-13 Raphael A. Hauser , Armin Eftekhari , Heinrich F. Matzinger

Principal Component Analysis (PCA) has wide applications in machine learning, text mining and computer vision. Classical PCA based on a Gaussian noise model is fragile to noise of large magnitude. Laplace noise assumption based PCA methods…

Machine Learning · Computer Science 2014-12-22 Pengtao Xie , Eric Xing

Principal component analysis (PCA) is a longstanding and well-studied approach for dimension reduction. It rests upon the assumption that the underlying signal in the data has low rank, and thus can be well-summarized using a small number…

Methodology · Statistics 2025-08-14 Ronan Perry , Snigdha Panigrahi , Jacob Bien , Daniela Witten

We present two diagnostic methods based on ideas of Principal Component Analysis and demonstrate their efficiency for sophisticated processing of multicolour photometric observations of variable objects.

Astrophysics · Physics 2015-06-24 Zdenek Mikulasek

Covariance matrix estimation and principal component analysis (PCA) are two cornerstones of multivariate analysis. Classic textbook solutions perform poorly when the dimension of the data is of a magnitude similar to the sample size, or…

Statistics Theory · Mathematics 2014-06-25 Olivier Ledoit , Michael Wolf

The variability of blazars in the X-ray and optical regions informs both the physics of their emitting region and places demands on the observer if a program requires that the object be bright or faint. The extensive simultaneous X-ray and…

High Energy Astrophysical Phenomena · Physics 2022-05-31 Kaitlyn E. Moo , Joel N. Bregman , Mark T. Reynolds

We present the results of a study to optimize the principal component analysis (PCA) algorithm for planet detection, a new algorithm complementing ADI and LOCI for increasing the contrast achievable next to a bright star. The stellar PSF is…

Earth and Planetary Astrophysics · Physics 2015-06-17 T. Meshkat , M. Kenworthy , S. P. Quanz , A. Amara

Based on some new robust estimators of the covariance matrix, we propose stable versions of Principal Component Analysis (PCA) and we qualify it independently of the dimension of the ambient space. We first provide a robust estimator of the…

Statistics Theory · Mathematics 2015-11-20 Ilaria Giulini