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Related papers: Generalised shape theory via pseudo-Wishart distri…

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We introduced a generalized Wishart distribution, namely, the Kotz-Wishart distribution. Several existing results based on the normality assumption have been extended. Inspired by the particular form of the pdf of the Kotz-Wishart matrix,…

Statistics Theory · Mathematics 2014-04-18 Amadou Sarr

A characterization of the existence of non-central Wishart distributions (with shape and non-centrality parameter) as well as the existence of solutions to Wishart stochastic differential equations (with initial data and drift parameter) in…

Probability · Mathematics 2019-01-29 Piotr Graczyk , Jacek Malecki , Eberhard Mayerhofer

Regularization is a common tool in variational inverse problems to impose assumptions on the parameters of the problem. One such assumption is sparsity, which is commonly promoted using lasso and total variation-like regularization.…

Statistics Theory · Mathematics 2023-02-15 Jasper Marijn Everink , Yiqiu Dong , Martin Skovgaard Andersen

In this paper a new approach is derived in the context of shape theory. The implemented methodology is motivated in an open problem proposed in \citet{GM93} about the construction of certain shape density involving Euler hypergeometric…

Statistics Theory · Mathematics 2015-02-04 Francisco J. Caro-Lopera , José A. Díaz-García

Generalised uncorrelated Wishart matrices are formed out of rectangular standard Gaussian data matrices with a certain pattern of zero entries. Development of the theory in the real and complex cases has proceeded along separate line. For…

Mathematical Physics · Physics 2024-10-02 Peter J. Forrester

A new potential is presented for spherical galaxies. The technique of the construction of our model is similar to that given by An and Evans. In a special case, its mass density becomes a special one of the Hernquist model. Another special…

Astrophysics of Galaxies · Physics 2025-03-11 Zhenglu Jiang , Zanchen Zhuo

Azzalini & Dalla Valle (1996) have recently discussed the multivariate skew-normal distribution which extends the class of normal distributions by the addition of a shape parameter. The first part of the present paper examines further…

Methodology · Statistics 2009-11-12 Adelchi Azzalini , Antonella Capitanio

Non-linear gravitational collapse introduces non-Gaussian statistics into the matter fields of the late Universe. As the large-scale structure is the target of current and future observational campaigns, one would ideally like to have the…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-12 Elena Sellentin , Andrew H. Jaffe , Alan F. Heavens

This paper is concerned with the study of a circular random distribution called geodesic Normal distribution recently proposed for general manifolds. This distribution, parameterized by two real numbers associated to some specific location…

Statistics Theory · Mathematics 2012-02-27 Jean-François Coeurjolly , Nicolas Le Bihan

A new method for analyzing point patterns produced by the evolution of gravitational clustering is presented. The method is taken from the study of molecular liquids, where it has been introduced for making a statistical description of…

Astrophysics · Physics 2009-10-31 R. Valdarnini

The work presents two examples of simple mathematical formulas which are natural nonlinear modifications (one being a generalization) of Gielis' formula. These formulas involve a comparable number of parameters and provide non-Platonic…

Adaptation and Self-Organizing Systems · Physics 2007-05-23 R. Chacon

While nonlinear optical spectroscopy is becoming more commonly used to study the excited states of nonlinear-optical systems, a general theory of inhomogeneous broadening is rarely applied in lieu of either a simple Lorentzian or Gaussian…

Optics · Physics 2008-02-26 Robert J. Kruhlak , Mark G. Kuzyk

We have developed a method based on wavelets to obtain the true underlying smooth density from a point distribution. The goal has been to reconstruct the density field in an optimal way ensuring that the morphology of the reconstructed…

Astrophysics · Physics 2009-11-13 V. J. Martinez , J. -L. Starck , E. Saar , D. L. Donoho , S. Reynolds , P. de la Cruz , S. Paredes

A generalization of the notion of ellipsoids to curved Riemannian spaces is given and the possibility to use it in describing the shapes of rotating bodies in general relativity is examined. As an illustrative example, stationary,…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Jozsef Zsigrai

In this paper we review the extent to which one can use classical distribution theory in describing solutions of Einstein's equations. We show that there are a number of physically interesting cases which cannot be treated using…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Roland Steinbauer , James A. Vickers

The central limit theorem provides the theoretical foundation for the universality of the normal distribution: under broad conditions, the asymptotic distribution of a sum of independent random variables approaches a Gaussian. Yet, physical…

Data Analysis, Statistics and Probability · Physics 2026-03-26 Mario Castro , José A. Cuesta

We study generalized symmetries in a simplified arena in which the usual quantum field theories of physics are replaced with topological field theories and the smooth structure with which the symmetry groups of physics are usually endowed…

High Energy Physics - Theory · Physics 2023-03-29 Ben Gripaios , Oscar Randal-Williams , Joseph Tooby-Smith

The shape of an object is an important characteristic for many vision problems such as segmentation, detection and tracking. Being independent of appearance, it is possible to generalize to a large range of objects from only small amounts…

Machine Learning · Statistics 2018-12-14 Alessandro Di Martino , Erik Bodin , Carl Henrik Ek , Neill D. F. Campbell

Theory of Newtonian dynamical systems admitting normal shift of hypersurfaces was first developed for the case of Riemannian manifolds. Recently it was generalized for manifolds geometric equipment of which is given by some regular…

Differential Geometry · Mathematics 2007-05-23 Ruslan Sharipov

This paper examines the classical matching distribution arising in the "problem of coincidences". We generalise the classical matching distribution with a preliminary round of allocation where items are correctly matched with some fixed…

Other Statistics · Statistics 2021-12-24 Ben O'Neill