Blind Additive Gaussian White Noise Level Estimation from a Single Image by Employing Chi-Square Distribution [PDF]
Entropy, 2022 The additive Gaussian white noise (AGWN) level in real-life images is usually unknown, for which the empirical setting will make the denoising methods over-smooth fine structures or remove noise incompletely.
Zhicheng Wang +4 more
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Chi-square, Student and Fisher-Snedecor Statistical Distributions and Their Application
Статистика України, 2018 The Chi-square distribution is the distribution of the sum of squared standard normal deviates. The degree of freedom of the distribution is equal to the number of standard normal deviates being summed. For the first time this distribution was studied by
F. V. Motsnyi
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On the computation of moments of the partial non-central chi-squared distribution function [PDF]
, 2013 Properties satisfied by the moments of the partial non-central chi-square distribution function, also known as Nuttall Q-functions, and methods for computing these moments are discussed in this paper.
Amparo Gil +2 more
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On the Convergence of the Chi Square and Noncentral Chi Square Distributions to the Normal Distribution [PDF]
IEEE Communications Letters, 2013 A simple and novel asymptotic bound for the maximum error resulting from the use of the central limit theorem to approximate the distribution of chi square and noncentral chi square random variables is derived. The bound enables the quick calculation of the number of degrees of freedom required to ensure a given approximation error, and is ...
Horgan, Donagh, Murphy, Colin C.
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Chi-Square Approximation for the Distribution of Individual Eigenvalues of a Singular Wishart Matrix [PDF]
MathematicsThis paper discusses the approximate distributions of eigenvalues of a singular Wishart matrix. We give the approximate joint density of eigenvalues by Laplace approximation for the hypergeometric functions of matrix arguments.
Koki Shimizu, Hiroki Hashiguchi
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The Distribution of a Linear Combination ofTwo Correlated Chi-Square Variables
Revista Colombiana de Estadística, 2013 The distribution of the linear combination of two chi-square variables is known if the variables are independent. In this paper, we derive the distribution of positive linear combination of two chi-square variables when they are correlated through a ...
ANWAR H. JOARDER +2 more
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An Adaptive Filter for Image Noise Removal Using Chi-Square Goodness-of-Fit to Uniform Distribution [PDF]
Engineering and Technology Journal, 2013 Noise is any undesired information that contaminates an image. The ideal situation (no noise) never occurs in practice, so there is a little point in ignoring it. Hence, one of the primary concerns of digital image processing is to increase image quality
Abdulameer A. Kareem +2 more
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NON-CENTRAL MULTIVARIATE CHI-SQUARE AND GAMMA DISTRIBUTIONS [PDF]
Far East Journal of Theoretical Statistics, 2016 15 ...
Thomas Royen
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Computation of cumulative density of noncentral chi-square distribution in Excel [PDF]
Tutorials in Quantitative Methods for Psychology, 2022 Noncentral distributions are obtained by transformation of their respective central distributions, and are identified by a noncentrality parameter. The noncentrality parameter measures the degree to which mean of test statistics departs, when the null ...
Sambaraju, Prasanth
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Performance analysis of WSN–FSO system modeled by Gamma–Chi-square channel distribution [PDF]
Proceedings of the Estonian Academy of Sciences, 2023 This paper presents the WSNâFSO (wireless sensor networkâfree-space optics) system based on CCR (corner cube retroreflector) and modeled with GammaâChi-square distribution.
Jelena Todorović +4 more
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