Polynomial bivariate copulas of degree five: characterization and some particular inequalities

Autor: Manuel Kauers, Radko Mesiar, Anna Kolesárová, Erich Peter Klement, Susanne Saminger-Platz, Adam Šeliga
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Dependence Modeling, Vol 9, Iss 1, Pp 13-42 (2021)
ISSN: 2300-2298
Popis: 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(x,y) =ax+by+c. The set of the parameters yielding a copula is characterized and visualized in detail. Polynomial copulas of degree 5 satisfying particular (in)equalities (symmetry, Schur concavity, positive and negative quadrant dependence, ultramodularity) are discussed and characterized. Then it is shown that for polynomial copulas of degree 5 the values of several dependence parameters (including Spearman’s rho, Kendall’s tau, Blomqvist’s beta, and Gini’s gamma) lie in exactly the same intervals as for the Eyraud-Farlie-Gumbel-Morgenstern copulas. Finally we prove that these dependence parameters attain all possible values in ]−1, 1[ if polynomial copulas of arbitrary degree are considered.
Databáze: OpenAIRE