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Related papers: Non-Gaussianity in SMICA

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Principal Component Analysis (PCA)-based techniques can separate data into different uncorrelated components and facilitate the statistical analysis as a pre-processing step. Independent Component Analysis (ICA) can separate statistically…

Instrumentation and Methods for Astrophysics · Physics 2023-01-03 Güray Hatipoğlu

We introduce coroICA, confounding-robust independent component analysis, a novel ICA algorithm which decomposes linearly mixed multivariate observations into independent components that are corrupted (and rendered dependent) by hidden…

Machine Learning · Statistics 2019-10-31 Niklas Pfister , Sebastian Weichwald , Peter Bühlmann , Bernhard Schölkopf

We consider the framework of Independent Component Analysis (ICA) for the case where the independent sources and their linear mixtures all reside in a Galois field of prime order P. Similarities and differences from the classical ICA…

Information Theory · Computer Science 2010-07-14 Arie Yeredor

Blind source separation (BSS) is a key technique in array processing and data analysis, aiming to recover unknown sources from observed mixtures without knowledge of the mixing matrix. Classical independent component analysis (ICA) methods…

Computer Vision and Pattern Recognition · Computer Science 2025-04-29 Zhongxuan Li

To create high-fidelity cosmic microwave background maps, current component separation methods rely on availability of information on different foreground components, usually through multi-band frequency coverage of the instrument. Internal…

Instrumentation and Methods for Astrophysics · Physics 2023-06-02 Guillermo F. Quispe Peña , Andrei V. Frolov

The power spectrum and bispectrum of dark matter tracers are key and complementary probes of the Universe. Next-generation surveys will deliver good measurements of the bispectrum, opening the door to improved cosmological constraints and…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-18 Dionysios Karagiannis , Roy Maartens , José Fonseca , Stefano Camera , Chris Clarkson

Blind source separation (BSS) techniques aims at joint estimation of source signals and a mixing matrix from observations of mixtures. This paper addresses a doubly nonstationary BSS problem, where the mixing matrix is time dependent and…

Signal Processing · Electrical Eng. & Systems 2019-06-25 Adrien Meynard

A convincing detection of primordial non-Gaussianity in the cosmic background radiation (CMB) is essential to probe the physics of the early universe. Since a single statistical estimator can hardly be suitable to detect the various…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-11 W. Cardona , A Bernui , M. J. Reboucas

This paper deals with a source separation strategy based on second-order statistics, namely, on data covariance matrices estimated at several lags. In general, ``blind'' approaches to source separation do not assume any knowledge on the…

Astrophysics · Physics 2009-11-10 L. Bedini , D. Herranz , E. Salerno , C. Baccigalupi , E. E. Kuruouglu , A. Tonazzini

Upcoming surveys will measure the cosmic microwave background (CMB) weak lensing power spectrum in exquisite detail, allowing for strong constraints on the sum of neutrino masses among other cosmological parameters. Standard CMB lensing…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-23 Delon Shen , Emmanuel Schaan , Simone Ferraro

The direct evaluation of manifestly optimal, cut-sky CMB power spectrum and bispectrum estimators is numerically very costly, due to the presence of inverse-covariance filtering operations. This justifies the investigation of alternative…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-01 H. F. Gruetjen , J. R. Fergusson , M. Liguori , E. P. S. Shellard

Lensing of the CMB generates a significant bispectrum, which should be detected by the Planck satellite at the 5-sigma level and is potentially a non-negligible source of bias for f_NL estimators of local non-Gaussianity. We extend current…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Antony Lewis , Anthony Challinor , Duncan Hanson

In the last decade, the study of cosmic microwave background (CMB) data has become one of the most powerful tools to study and understand the Universe. More precisely, measuring the CMB power spectrum leads to the estimation of most…

Astrophysics · Physics 2009-11-13 J. Bobin , Y. Moudden , J. -L. Starck , J. Fadili , N. Aghanim

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

Independent Component Analysis (ICA) aims to find a coordinate system in which the components of the data are independent. In this paper we construct a new nonlinear ICA model, called WICA, which obtains better and more stable results than…

Machine Learning · Computer Science 2020-12-11 Andrzej Bedychaj , Przemysław Spurek , Aleksandra Nowak , Jacek Tabor

The success of machine learning models relies heavily on effectively representing high-dimensional data. However, ensuring data representations capture human-understandable concepts remains difficult, often requiring the incorporation of…

Machine Learning · Statistics 2024-11-01 Jiayu Su , David A. Knowles , Raul Rabadan

We present a new method for multi-component power spectra estimation in multi-frequency observations of the CMB. Our method is based on matching a model to the cross and auto power spectra of observed maps. All the component power spectra…

Astrophysics · Physics 2015-06-24 Guillaume Patanchon

In the recent years, non-Gaussianity and statistical isotropy of the Cosmic Microwave Background (CMB) was investigated with various statistical measures, first and foremost by means of the measurements of the WMAP satellite. In this…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-21 G. Rossmanith , H. Modest , C. Raeth , A. J. Banday , K. M. Gorski , G. Morfill

Application of independent component analysis (ICA) as an unmixing and image clustering technique for high spatial resolution Raman maps is reported. A hyperspectral map of a fixed human cell was collected by a Raman micro spectrometer in a…

Quantitative Methods · Quantitative Biology 2022-01-02 M. Hamed Mozaffari , Li-Lin Tay

We present a Gibbs sampling solution to the map-making problem for CMB measurements, building on existing destriping methodology. Gibbs sampling breaks the computationally heavy destriping problem into two separate steps; noise filtering…