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Asymptotic study of canonical correlation analysis: from matrix and analytic approach to operator and tensor approach.

Jeanne Fine (2003)

SORT

Asymptotic study of canonical correlation analysis gives the opportunity to present the different steps of an asymptotic study and to show the interest of an operator and tensor approach of multidimensional asymptotic statistics rather than the classical, matrix and analytic approach. Using the last approach, Anderson (1999) assumes the random vectors to have a normal distribution and the non zero canonical correlation coefficients to be distinct. The new approach we use, Fine (2000), is coordinate-free,...

Basic bounds of Fréchet classes

Jaroslav Skřivánek (2014)

Kybernetika

Algebraic bounds of Fréchet classes of copulas can be derived from the fundamental attributes of the associated copulas. A minimal system of algebraic bounds and related basic bounds can be defined using properties of pointed convex polyhedral cones and their relationship with non-negative solutions of systems of linear homogeneous Diophantine equations, largely studied in Combinatorics. The basic bounds are an algebraic improving of the Fréchet-Hoeffding bounds. We provide conditions of compatibility...

Bivariate copulas, norms and non-exchangeability

Pier Luigi Papini (2015)

Dependence Modeling

The present paper is related to the study of asymmetry for copulas by introducing functionals based on different norms for continuous variables. In particular, we discuss some facts concerning asymmetry and we point out some flaws occurring in the recent literature dealing with this matter.

Bivariate copulas: Transformations, asymmetry and measures of concordance

Sebastian Fuchs, Klaus D. Schmidt (2014)

Kybernetika

The present paper introduces a group of transformations on the collection of all bivariate copulas. This group contains an involution which is particularly useful since it provides (1) a criterion under which a given symmetric copula can be transformed into an asymmetric one and (2) a condition under which for a given copula the value of every measure of concordance is equal to zero. The group also contains a subgroup which is of particular interest since its four elements preserve symmetry, the...

Block matrix approximation via entropy loss function

Malwina Janiszewska, Augustyn Markiewicz, Monika Mokrzycka (2020)

Applications of Mathematics

The aim of the paper is to present a procedure for the approximation of a symmetric positive definite matrix by symmetric block partitioned matrices with structured off-diagonal blocks. The entropy loss function is chosen as approximation criterion. This procedure is applied in a simulation study of the statistical problem of covariance structure identification.

Bounds of general Fréchet classes

Jaroslav Skřivánek (2012)

Kybernetika

This paper deals with conditions of compatibility of a system of copulas and with bounds of general Fréchet classes. Algebraic search for the bounds is interpreted as a solution to a linear system of Diophantine equations. Classical analytical specification of the bounds is described.

Characterizations of Archimedean n -copulas

Włodzimierz Wysocki (2015)

Kybernetika

We present three characterizations of n -dimensional Archimedean copulas: algebraic, differential and diagonal. The first is due to Jouini and Clemen. We formulate it in a more general form, in terms of an n -variable operation derived from a binary operation. The second characterization is in terms of first order partial derivatives of the copula. The last characterization uses diagonal generators, which are “regular” diagonal sections of copulas, enabling one to recover the copulas by means of an...

Componentwise concave copulas and their asymmetry

Fabrizio Durante, Pier Luigi Papini (2009)

Kybernetika

The class of componentwise concave copulas is considered, with particular emphasis on its closure under some constructions of copulas (e.g., ordinal sum) and its relations with other classes of copulas characterized by some notions of concavity and/or convexity. Then, a sharp upper bound is given for the L ∞ -measure of non-exchangeability for copulas belonging to this class.

Conception et analyse de la forme limite d'une famille de coefficients statistiques d'association entre variables relationnelles. II

Israël-César Lerman (1992)

Mathématiques et Sciences Humaines

Cette étude offre une large vision de synthèse prospective ; mais aussi, des résultats techniques précis sur une famille très générale que nous avons élaborée de coefficients d'association entre variables descriptives relationnelles à partir de leur observation empirique sur un ensemble O d'objets élémentaires. Un même coefficient est obtenu à partir d'une forme de normalisation statistique par rapport à une hypothèse d'absence de liaison, d'un indice brut d'association. Ce dernier suppose une représentation...

Conception et analyse de la forme limite d'une famille de coefficients statistiques d'association entre variables relationnelles. 1ère partie

Israël-César Lerman (1992)

Mathématiques et Sciences Humaines

Cette étude offre une large vision de synthèse prospective : mais aussi, des résultats techniques précis sur une famille très générale que nous avons élaborée de coefficients d'association entre variables descriptives relationnelles à partir de leur observation empirique sur un ensemble O d'objets élémentaires. Un même coefficient est obtenu à partir d'une forme de normalisation statistique par rapport à une hypothèse d'absence de liaison, d'un indice brut d'association. Ce dernier suppose une représentation...

Congruences and ideals in lattice effect algebras as basic algebras

Sylvia Pulmannová, Elena Vinceková (2009)

Kybernetika

Effect basic algebras (which correspond to lattice ordered effect algebras) are studied. Their ideals are characterized (in the language of basic algebras) and one-to-one correspondence between ideals and congruences is shown. Conditions under which the quotients are OMLs or MV-algebras are found.

Constructing copulas by means of pairs of order statistics

Ali Dolati, Manuel Úbeda-Flores (2009)

Kybernetika

In this paper, we introduce two transformations on a given copula to construct new and recover already-existent families. The method is based on the choice of pairs of order statistics of the marginal distributions. Properties of such transformations and their effects on the dependence and symmetry structure of a copula are studied.

Constructing families of symmetric dependence functions

Włodzimierz Wysocki (2012)

Kybernetika

We construct two pairs ( 𝒜 F [ 1 ] , 𝒜 F [ 2 ] ) and ( 𝒜 ψ [ 1 ] , 𝒜 ψ [ 2 ] ) of ordered parametric families of symmetric dependence functions. The families of the first pair are indexed by regular distribution functions F , and those of the second pair by elements ψ of a specific function family ψ . We also show that all solutions of the differential equation d y d u = α ( u ) u ( 1 - u ) y for α in a certain function family α s are symmetric dependence functions.

Currently displaying 21 – 40 of 138