English
Related papers

Related papers: Non-Gaussian Chi-squared method with the multivari…

200 papers

Following the discovery of the CMB, the hot big-bang model has become the standard cosmological model. In this theory, small primordial fluctuations are subsequently amplified by gravity to form the large-scale structure seen today.…

Astrophysics · Physics 2015-06-24 Licia Verde

In this paper we derive an exact full expression for the 2D probability distribution of the ellipticity of an object measured from data, only assuming Gaussian noise in pixel values. This is a generalisation of the probability distribution…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Massimo Viola , Thomas Kitching , Benjamin Joachimi

In this study, we develop nonparametric analysis of deviance tools for generalized partially linear models based on local polynomial fitting. Assuming a canonical link, we propose expressions for both local and global analysis of deviance,…

Statistics Theory · Mathematics 2020-09-10 Wolfgang Karl Härdle , Li-Shan Huang

Primordial, non-Gaussian perturbations can generate scale-dependent bias in the galaxy distribution. This in turn will modify correlations between galaxy positions and peculiar velocities at late times, since peculiar velocities reflect the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Yin-Zhe Ma , James E. Taylor , Douglas Scott

We study the significance of non-Gaussianity in the likelihood of weak lensing shear two-point correlation functions, detecting significantly non-zero skewness and kurtosis in one-dimensional marginal distributions of shear two-point…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 Chien-Hao Lin , Joachim Harnois-Déraps , Tim Eifler , Taylor Pospisil , Rachel Mandelbaum , Ann B. Lee , Sukhdeep Singh

In the mixture modeling frame, this paper presents the polynomial Gaussian cluster-weighted model (CWM). It extends the linear Gaussian CWM, for bivariate data, in a twofold way. Firstly, it allows for possible nonlinear dependencies in the…

Methodology · Statistics 2012-07-05 Antonio Punzo

Non-Gaussian likelihoods, ubiquitous throughout cosmology, are a direct consequence of nonlinearities in the physical model. Their treatment requires Monte-Carlo Markov-chain or more advanced sampling methods for the determination of…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-24 Lennart Röver , Lea Carlotta Bartels , Björn Malte Schäfer

Recent progresses in single particle tracking have shown evidences of non-Gaussian distribution of displacements in living cells, both near the cellular membrane and inside the cytoskeleton. A similar behavior has also been observed in…

Biological Physics · Physics 2019-05-30 Yann Lanoiselée , Denis S. Grebenkov

We apply various expansion schemes that may be used to study gravitational clustering to the simple case of the Zeldovich dynamics. Using the well-known exact solution of the Zeldovich dynamics we can compare the predictions of these…

Astrophysics · Physics 2009-11-13 Patrick Valageas

We develop a general method to quantify the uncertainties of parton distribution functions and their physical predictions, with emphasis on incorporating all relevant experimental constraints. The method uses the Hessian formalism to study…

High Energy Physics - Phenomenology · Physics 2008-12-18 J. Pumplin , D. Stump , R. Brock , D. Casey , J. Huston , J. Kalk , H. L. Lai , W. K. Tung

This survey reviews the existing literature on the most relevant Bayesian inference methods for univariate and multivariate GARCH models. The advantages and drawbacks of each procedure are outlined as well as the advantages of the Bayesian…

Statistics Theory · Mathematics 2014-02-04 Audronė Virbickaitė , M. Concepción Ausín , Pedro Galeano

The standard diffusive spreading, characterized by a Gaussian distribution with mean square displacement that grows linearly with time, can break down, for instance, under the presence of correlations and heterogeneity. In this work, we…

Statistical Mechanics · Physics 2021-10-27 M. A. F. dos Santos , E. H. Colombo , C. Anteneodo

The paper presents a new statistical method that enables the use of systematic errors in the maximum-likelihood regression of integer-count Poisson data to a parametric model. The method is primarily aimed at the characterization of the…

Instrumentation and Methods for Astrophysics · Physics 2024-07-18 Max Bonamente , Yang Chen , Dale Zimmerman

As a statistical measure to quantify the topological structure of the large-scale structure in the universe, the genus number is calculated for a number of non-Gaussian distributions in which the density field is characterized by a…

Astrophysics · Physics 2009-10-28 Takahiko Matsubara , Jun'ichi Yokoyama

The noncentral Wishart distribution has become more mainstream in statistics as the prevalence of applications involving sample covariances with underlying multivariate Gaussian populations as dramatically increased since the advent of…

Statistics Theory · Mathematics 2022-05-25 Frédéric Ouimet

We demonstrate that two approximations to the chi^2 statistic as popularly employed by observational astronomers for fitting Poisson-distributed data can give rise to intrinsically biased model parameter estimates, even in the high counts…

Astrophysics · Physics 2009-11-13 Philip J. Humphrey , Wenhao Liu , David A. Buote

We propose a flexible formulation of the multivariate non-central skew t (NCST) distribution, defined by scaling skew-normal random vectors with independent chi-squared variables. This construction extends the classical multivariate t…

Methodology · Statistics 2025-07-15 Abeer M. Hasan , Ying-Ju Chen

Diffusion models have emerged as powerful tools for solving inverse problems, yet prior work has primarily focused on observations with Gaussian measurement noise, restricting their use in real-world scenarios. This limitation persists due…

Machine Learning · Statistics 2025-02-11 Alessandro Micheli , Mélodie Monod , Samir Bhatt

A growing number of biological, soft, and active matter systems are observed to exhibit normal diffusive dynamics with a linear growth of the mean squared displacement, yet with a non-Gaussian distribution of increments. Based on the…

Statistical Mechanics · Physics 2017-04-12 A. V. Chechkin , F. Seno , R. Metzler , I. M. Sokolov

We consider a cosmological model with non-Gaussian initial perturbations, which in principle could be generated in non-standard inflationary scenarios with two or more scalar fields. In particular we focus our attention on the model…

Astrophysics · Physics 2011-05-10 Dmitri Novikov , Jens Schmalzing , Viatcheslav F. Mukhanov