Results 11 to 20 of about 25,546 (258)
New Families of Bivariate Copulas via Unit Lomax Distortion
Risks, 2020 This article studies a new family of bivariate copulas constructed using the unit-Lomax distortion derived from a transformation of the non-negative Lomax random variable into a variable whose support is the unit interval.
Fadal Abdullah-A Aldhufairi +2 more
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Polynomial bivariate copulas of degree five: characterization and some particular inequalities
Dependence Modeling, 2021 Bivariate polynomial copulas of degree 5 (containing the family of Eyraud-Farlie-Gumbel-Morgenstern copulas) are in a one-to-one correspondence to certain real parameter triplets (a, b, c), i.e., to some set of polynomials in two variables of degree 1: p(
Šeliga Adam +5 more
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On the Size of Subclasses of Quasi-Copulas and Their Dedekind–MacNeille Completion
Mathematics, 2020 We study some topological properties of the class of supermodular n-quasi-copulas and check that the topological size of the Dedekind–MacNeille completion of the set of n-copulas is small, in terms of the Baire category, in the Dedekind–MacNeille ...
Fabrizio Durante +3 more
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Is a Normal Copula the Right Copula? [PDF]
Journal of Business & Economic Statistics, 2018 We derive computationally simple and intuitive expressions for score tests of Gaussian copulas against Generalized Hyperbolic alternatives, including symmetric and asymmetric Student t, and many other examples. We decompose our tests into third and fourth moment components, and obtain one-sided Likelihood Ratio analogues, whose standard asymptotic ...
Amengual, Dante, Sentana, Enrique
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The t Copula and Related Copulas
International Statistical Review, 2007 Summary: The \(t\) copula and its properties are described with a focus on issues related to the dependence of extreme values. The Gaussian mixture representation of a multivariate \(t\) distribution is used as a starting point to construct two new copulas, the skewed \(t\) copula and the grouped \(t\) copula, which allow more heterogeneity in the ...
Demarta, Stefano, Mcneil, Alexander J.
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New asymmetric perturbations of FGM bivariate copulas and concordance preserving problems
Moroccan Journal of Pure and Applied Analysis, 2023 New copulas, based on perturbation theory, are introduced to clarify a symmetrization procedure for asymmetric copulas. We give also some properties of the symmetrized copula mainly conservation of concordance.
El maazouz Mohamed, Sani Ahmed
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Electronic Journal of Statistics, 2014 We propose notions of calibration for probabilistic forecasts of general multivariate quantities. Probabilistic copula calibration is a natural analogue of probabilistic calibration in the univariate setting. It can be assessed empirically by checking for the uniformity of the copula probability integral transform (CopPIT), which is invariant under ...
Johanna F. Ziegel, Tilmann Gneiting
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A Note on Upper Tail Behavior of Liouville Copulas
Risks, 2016 The family of Liouville copulas is defined as the survival copulas of multivariate Liouville distributions, and it covers the Archimedean copulas constructed by Williamson’s d-transform.
Lei Hua
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Baire category results for quasi–copulas
Dependence Modeling, 2016 The aim of this manuscript is to determine the relative size of several functions (copulas, quasi– copulas) that are commonly used in stochastic modeling.
Durante Fabrizio +2 more
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General Multivariate Dependence using Associated Copulas
Revstat Statistical Journal, 2016 This paper studies the general multivariate dependence and tail dependence of a random vector. We analyse the dependence of variables going up or down, covering the 2 d orthants of dimension d and accounting for non-positive dependence.
Yuri Salazar Flores
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