Results 11 to 20 of about 395 (64)
On a Separation Theorem for Delta-Convex Functions
In the present paper we establish necessary and sufficient conditions under which two functions can be separated by a delta-convex function. This separation will be understood as a separation with respect to the partial order generated by the Lorentz ...
Olbryś Andrzej
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In this paper, we give two weak conditions for a lower semi‐continuous function on the n‐dimensional Euclidean space Rn to be a convex function. We also present some results for convex functions, strictly convex functions, and quasi‐convex functions.
Yu-Ru Syau
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Polynomial bivariate copulas of degree five: characterization and some particular inequalities
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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Transformations which preserve convexity
Let C be the class of convex nondecreasing functions f : [0, ∞) → [0, ∞) which satisfy f(0) = 0. Marshall and Proschan [1] determine the one‐to‐one and onto functions ψ : [0, ∞) → [0, ∞) such that g = ψ∘f∘ψ−1 belongs to C whenever f belongs to C. We study several natural models for multivariate extension of the Marshall‐Proschan result.
Robert A. Fontenot, Frank Proschan
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Nonlinear Sherman-type inequalities
An important class of Schur-convex functions is generated by convex functions via the well-known Hardy–Littlewood–Pólya–Karamata inequality. Sherman’s inequality is a natural generalization of the HLPK inequality.
Niezgoda Marek
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Characterization of balls through optimal concavity for potential functions [PDF]
Let $p\in(1,n)$. If $\Omega$ is a convex domain in $\rn$ whose $p$-capacitary potential function $u$ is $(1-p)/(n-p)$-concave (i.e. $u^{(1-p)/(n-p)}$ is convex), then $\Omega$ is a ball.
arxiv +1 more source
A primal-dual approach of weak vector equilibrium problems
In this paper we provide some new sufficient conditions that ensure the existence of the solution of a weak vector equilibrium problem in Hausdorff topological vector spaces ordered by a cone.
László Szilárd
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Characterizations of bivariate conic, extreme value, and Archimax copulas
Based on a general construction method by means of bivariate ultramodular copulas we construct, for particular settings, special bivariate conic, extreme value, and Archimax copulas. We also show that the sets of copulas obtained in this way are dense in
Saminger-Platz Susanne+3 more
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Optimality and duality in set-valued optimization utilizing limit sets
This paper deals with optimality conditions and duality theory for vector optimization involving non-convex set-valued maps. Firstly, under the assumption of nearly cone-subconvexlike property for set-valued maps, the necessary and sufficient optimality ...
Kong Xiangyu, Zhang Yinfeng, Yu GuoLin
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Characterizations of minimal elements of upper support with applications in minimizing DC functions
In this study, we discuss on the problem of minimizing the differences of two non-positive valued increasing, co-radiant and quasi-concave (ICRQC) functions defined on XX (where XX is a real locally convex topological vector space).
Mirzadeh Somayeh+2 more
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