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Related papers: Independent Component Analysis by Wavelets

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We estimate on a compact interval densities with isolated irregularities, such as discontinuities or discontinuities in some derivatives. From independent and identically distributed observations we construct a kernel estimator with…

Statistics Theory · Mathematics 2024-07-16 Céline Duval , Émeline Schmisser

Independent component analysis (ICA) has often been used as a tool to model natural image statistics by separating multivariate signals in the image into components that are assumed to be independent. However, these estimated components…

Computer Vision and Pattern Recognition · Computer Science 2019-01-25 Zhimin Chen , Darius Parvin , Maedbh King , Susan Hao

We propose a new wavelet-based method for density estimation when the data are size-biased. More specifically, we consider a power of the density of interest, where this power exceeds 1/2. Warped wavelet bases are employed, where warping is…

Methodology · Statistics 2022-12-08 Michel H. Montoril , Aluísio Pinheiro , Brani Vidakovic

A data-driven block thresholding procedure for wavelet regression is proposed and its theoretical and numerical properties are investigated. The procedure empirically chooses the block size and threshold level at each resolution level by…

Statistics Theory · Mathematics 2009-03-31 T. Tony Cai , Harrison H. Zhou

We investigate the posterior rate of convergence for wavelet shrinkage using a Bayesian approach in general Besov spaces. Instead of studying the Bayesian estimator related to a particular loss function, we focus on the posterior…

Statistics Theory · Mathematics 2007-09-24 Heng Lian

The Independent Component Analysis (ICA) algorithm is implemented as a neural network for separating signals of different origin in astrophysical sky maps. Due to its self-organizing capability, it works without prior assumptions on the…

The statistical dependencies which independent component analysis (ICA) cannot remove often provide rich information beyond the linear independent components. It would thus be very useful to estimate the dependency structure from data.…

Machine Learning · Statistics 2017-07-28 Hiroaki Sasaki , Michael U. Gutmann , Hayaru Shouno , Aapo Hyvärinen

For given computational resources, the accuracy of plasma simulations using particles is mainly held back by the noise due to limited statistical sampling in the reconstruction of the particle distribution function. A method based on…

Computational Physics · Physics 2009-09-03 Romain Nguyen van yen , Diego del-Castillo-Negrete , Kai Schneider , Marie Farge , Guangye Chen

We consider an inverse problem for the linear one-dimensional wave equation with variable coefficients consisting in determining an unknown source term from a boundary observation. A method to obtain approximations of this inverse problem…

Numerical Analysis · Mathematics 2025-01-22 Carlos Castro , Sorin Micu

In this note the ILC's capabilities for detecting WIMPs and measuring their properties are studied. The expected signal cross section is derived in a model-independent way from the observed relic density of Dark Matter. Signal events are…

High Energy Physics - Experiment · Physics 2009-02-02 C. Bartels , J. List

The identification of increasingly smaller signal from objects observed with a non-perfect instrument in a noisy environment poses a challenge for a statistically clean data analysis. We want to compute the probability of frequencies…

Astrophysics · Physics 2010-06-29 P. Reegen , M. Gruberbauer , L. Schneider , W. W. Weiss

In this paper we update the existing schemes for computation of atom-interferometric signal in single-atom interferometers to interferometry with dense Bose-condensed atomic samples. Using the theory developed we explain the fringe contrast…

Other Condensed Matter · Physics 2007-05-23 Maxim Olshanii , Vanja Dunjko

The literature on statistical learning for time series often assumes asymptotic independence or "mixing" of the data-generating process. These mixing assumptions are never tested, nor are there methods for estimating mixing coefficients…

Statistics Theory · Mathematics 2016-02-09 Daniel J. McDonald , Cosma Rohilla Shalizi , Mark Schervish

Here, a separation theorem about Independent Subspace Analysis (ISA), a generalization of Independent Component Analysis (ICA) is proven. According to the theorem, ISA estimation can be executed in two steps under certain conditions. In the…

Statistics Theory · Mathematics 2007-06-13 Zoltan Szabo , Barnabas Poczos , Andras Lorincz

Cosine similarity is widely used to measure the similarity between two embeddings, while interpretations based on angle and correlation coefficient are common. In this study, we focus on the interpretable axes of embeddings transformed by…

Computation and Language · Computer Science 2024-12-18 Hiroaki Yamagiwa , Momose Oyama , Hidetoshi Shimodaira

In this work we study the relevance of the component separation technique based on the Independent Component Analysis (ICA) and investigate its performance in the context of a limited sky coverage observation and from the viewpoint of our…

Astrophysics · Physics 2009-11-11 Federico Stivoli , Carlo Baccigalupi , Davide Maino , Radek Stompor

Independent component analysis (ICA) is a fundamental statistical tool used to reveal hidden generative processes from observed data. However, traditional ICA approaches struggle with the rotational invariance inherent in Gaussian…

Machine Learning · Computer Science 2024-08-21 Ignavier Ng , Yujia Zheng , Xinshuai Dong , Kun Zhang

This paper explores a class of empirical Bayes methods for level-dependent threshold selection in wavelet shrinkage. The prior considered for each wavelet coefficient is a mixture of an atom of probability at zero and a heavy-tailed…

Statistics Theory · Mathematics 2007-06-13 Iain M. Johnstone , Bernard W. Silverman

In this paper, we derive a central limit theorem for collections of weakly correlated random variables indexed by discrete metric spaces, where the correlation decays in the distance of the indices. The correlation structure we study…

Probability · Mathematics 2022-02-11 Michael Fleermann , Werner Kirsch

In this paper, we study the problem of pointwise estimation of a multivariate density. We provide a data-driven selection rule from the family of kernel estimators and derive for it a pointwise oracle inequality. Using the latter bound, we…

Statistics Theory · Mathematics 2015-09-21 Gilles Rebelles