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Related papers: Using the COBE/DMR data as a test-bed for normalit…

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We introduce a new mathematical tool (a direction-dependent probe) to analyse the randomness of purported isotropic Gaussian random fields on the sphere. We apply the probe to assess the full-sky cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-29 J. Hamann , Q. T. Le Gia , I. H. Sloan , Y. G. Wang , R. S. Womersley

In gravitational wave astronomy, non-Gaussian noise, such as scattered light noise disturbs stable interferometer operation, limiting the interferometer's sensitivity, and reducing the reliability of the analyses. In scattered light noise,…

General Relativity and Quantum Cosmology · Physics 2024-03-20 Shunsei Yamamura , Hirotaka Yuzurihara , Takahiro Yamamoto , Takashi Uchiyama

Local scaling properties of the co-added foreground-cleaned three-year Wilkinson Microwave Anisotropy Probe (WMAP) data are estimated using weighted scaling indices. The scaling index method (SIM) is - for the first time - adapted and…

Astrophysics · Physics 2009-05-21 C. Raeth , P. Schuecker , A. J. Banday

The Gaussian graphical model is routinely employed to model the joint distribution of multiple random variables. The graph it induces is not only useful for describing the relationship between random variables but also critical for…

Methodology · Statistics 2022-12-15 Thien-Minh Le , Ping-Shou Zhong , Chenlei Leng

In (Hansen et al. 2002) we presented a new approach for measuring non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern, based on the multivariate empirical distribution function of the spherical harmonics a_lm of a…

Astrophysics · Physics 2010-11-19 Frode K. Hansen , Domenico Marinucci , Nicola Vittorio

We consider the problem of detecting the presence of a spatially correlated multichannel signal corrupted by additive Gaussian noise (i.i.d across sensors). No prior knowledge is assumed about the system parameters such as the noise…

Information Theory · Computer Science 2013-04-19 Vidyadhar Upadhya , Devendra Jalihal

We propose several pseudoentropy measures that agree well with the Wehrl entropy, but are significantly faster to compute. All of them are rotationally invariant measures of entanglement very sensitive to non-Gaussianity, anisotropy, and…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-06 Momchil Minkov , Marvin Pinkwart , Peter Schupp

Gaussian graphical models have been used to study intrinsic dependence among several variables, but the Gaussianity assumption may be restrictive in many applications. A nonparanormal graphical model is a semiparametric generalization for…

Methodology · Statistics 2020-05-20 Jami J. Mulgrave , Subhashis Ghosal

In this paper, a Bayesian semiparametric copula approach is used to model the underlying multivariate distribution $F_{true}$. First, the Dirichlet process is constructed on the unknown marginal distributions of $F_{true}$. Then a Gaussian…

Methodology · Statistics 2019-07-05 Luai Al-Labadi , Forough Fazeli Asl , Zahra Saberi

Using a discrete wavelet based space-scale decomposition (SSD), the spectrum of the skewness and kurtosis is developed to describe the non-Gaussian signatures in cosmologically interesting samples. Because the basis of the discrete wavelet…

Astrophysics · Physics 2007-05-23 Jesus Pando , Li-Zhi Fang

One of the most powerful tools to probe the existence of cosmic defects in the early universe is through the Cosmic Microwave Background (CMB) radiation. It is well known that computations with causal sources are more involved than the…

Astrophysics · Physics 2007-05-23 Alejandro Gangui

To improve the identification of potential anomaly patterns in complex user behavior, this paper proposes an anomaly detection method based on a deep mixture density network. The method constructs a Gaussian mixture model parameterized by a…

Machine Learning · Computer Science 2025-05-20 Lu Dai , Wenxuan Zhu , Xuehui Quan , Renzi Meng , Sheng Chai , Yichen Wang

System identification is of special interest in science and engineering. This article is concerned with a system identification problem arising in stochastic dynamic systems, where the aim is to estimate the parameters of a system along…

Methodology · Statistics 2022-01-27 Christos Merkatas , Simo Särkkä

Currently, it appears that the best method for non-Gaussianity detection in the Cosmic Microwave Background (CMB) consists in calculating the kurtosis of the wavelet coefficients. We know that wavelet-kurtosis outperforms other methods such…

Astrophysics · Physics 2016-02-17 J. Jin , J. -L. Starck , D. L. Donoho , N. Aghanim , O. Forni

Anomalies are strange data points; they usually represent an unusual occurrence. Anomaly detection is presented from the perspective of Wireless sensor networks. Different approaches have been taken in the past, as we will see, not only to…

Machine Learning · Computer Science 2017-08-30 Pelumi Oluwasanya

In fiber-optic distributed sensing, vibration signals are mostly assumed to follow Gaussian distribution for the simplicity of signal processing. However, in real applications, vibration signals often behave as non-Gaussian processes, which…

Signal Processing · Electrical Eng. & Systems 2019-01-18 Qian He , Rong Liu , Chengdan Tan , Lijun Tang , Xiongjun Shang

After the precise observations of the Cosmic Microwave Background (CMB) anisotropy power spectrum, attention is now being focused on the higher order statistics of the CMB anisotropies. Since linear evolution preserves the statistical…

Astrophysics · Physics 2009-11-10 Daniel Babich , Matias Zaldarriaga

We review the basic hypotheses which motivate the statistical framework used to analyze the cosmic microwave background, and how that framework can be enlarged as we relax those hypotheses. In particular, we try to separate as much as…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 L. Raul Abramo , Thiago S. Pereira

We propose a Bayesian test of normality for univariate or multivariate data against alternative nonparametric models characterized by Dirichlet process mixture distributions. The alternative models are based on the principles of embedding…

Statistics Theory · Mathematics 2023-04-12 Surya T. Tokdar , Ryan Martin

The COBE-DMR 4-year maps displayed a strong non-Gaussian signal in the ``inter-scale'' components of the bispectrum: their observed values did not display the scatter expected from Gaussian maps. We re-examine this and other suggested…

Astrophysics · Physics 2016-08-16 João Magueijo , João Medeiros