Results 61 to 70 of about 961 (151)

Local subdifferentials and multivariational inequalities in Banach and Frechet spaces [PDF]

Opuscula Mathematica, 2008
Some functional-topological concepts of subdifferential and locally subdifferential maps in Frechet spaces are established. Multivariational inequalities with an operator of the pseudo-monotone type, connected with subdifferential maps, are considered.
Pavlo O. Kasyanov, Valery S. Mel'nik, Anna M. Piccirillo   +2 more
doaj  

Sequential Outlier Detection in Nonstationary Time Series

Journal of Time Series Analysis, EarlyView.
ABSTRACT A novel method for sequential outlier detection in nonstationary time series is proposed. The method tests the null hypothesis of “no outlier” at each time point, addressing the multiple testing problem by bounding the error probability of successive tests, using extreme‐value theory. The asymptotic properties of the test statistic are studied
Florian Heinrichs, Patrick Bastian, Holger Dette   +2 more
wiley   +1 more source

Testing Distributional Granger Causality With Entropic Optimal Transport

Journal of Time Series Analysis, EarlyView.
ABSTRACT We develop a novel nonparametric test for Granger causality in distribution based on entropic optimal transport. Unlike classical mean‐based approaches, the proposed method directly compares the full conditional distributions of a response variable with and without the history of a candidate predictor.
Tao Wang
wiley   +1 more source

A Theory for Interpolation of Metric Spaces

Axioms
In this work, we develop an interpolation theory for metric spaces inspired by the real method of interpolation. These interpolation spaces preserve Lipschitz operators under certain conditions.
Robledo Mak’s Miranda Sette, Dicesar Lass Fernandez, Eduardo Brandani da Silva   +2 more
doaj   +1 more source

Robust Mean–Variance Portfolio Optimization: Mean–Variance–Variance Criterion Versus Mean–Variance–Standard Deviation Criterion

Mathematical Finance, EarlyView.
ABSTRACT We study a dynamic portfolio optimization problem under the mean–variance–variance (M‐V‐V) criterion proposed by Maccheroni et al. It is an analogue of the Arrow–Pratt approximation to the well‐known smooth ambiguity model. Under the standard Black–Scholes framework, we derive fully explicit equilibrium investment strategies in which a DM's ...
David Landriault, Bin Li, Yuanyuan Zhang
wiley   +1 more source

Edge‐Length Preserving Embeddings of Graphs Between Normed Spaces

Journal of Graph Theory, Volume 112, Issue 4, Page 491-506, August 2026.
ABSTRACT The concept of graph embeddability, initially formalized by Belk and Connelly and later expanded by Sitharam and Willoughby, extends the question of embedding finite metric spaces into a given normed space. A finite simple graph G = ( V , E ) is said to be ( X , Y )‐embeddable if any set of induced edge lengths from an embedding of G into a ...
Sean Dewar, Eleftherios Kastis, Derek Kitson, William Sims   +3 more
wiley   +1 more source

On Fuzzy Fréchet Contractions Governed by Rational Expressions and Related Applications

Journal of Applied Science and Engineering
. This work explores a specific category of contraction mappings characterized by rational- type within the framework of fuzzy Fréchet spaces(FFS). By utilizing the triangular inequality associated with fuzzy seminorms, we establish fixed point results ...
Ahmed Ghanawi Jasim
doaj   +1 more source

On a System of Volterra Type Hadamard Fractional Integral Equations in Fréchet Spaces

Discrete Dynamics in Nature and Society, 2018
In this article we present some results concerning the existence of solutions for a system of Hadamard integral equations. Our investigation is conducted with an application of an extension of the fixed point theorem of Burton-Kirk in Fréchet spaces.
Saïd Abbas, Mouffak Benchohra, Yong Zhou   +2 more
doaj   +1 more source

On the Choice of Optimization Norm for Anderson Acceleration of the Picard Iteration for Navier–Stokes Equations

Numerical Methods for Partial Differential Equations, Volume 42, Issue 4, July 2026.
ABSTRACT While recent Anderson acceleration (AA) convergence theory [Pollock et al., IMA Num. An., 2021] requires that the AA optimization norm match the Hilbert space norm associated with the fixed point operator, in implementations the ℓ2$$ {\ell}^2 $$ norm is the most common choice. So far there is little research done regarding this discrepancy. To
Elizabeth Hawkins, Leo G. Rebholz
wiley   +1 more source

On I-Fréchet-Urysohn spaces and sequential I-convergence groups [PDF]

Mathematica Moravica, 2019
In this paper, we introduce the concept of sequential I-convergence spaces and I-Fréchet-Urysohn space and study their properties. We give a sufficient condition for the product of two sequential I-convergence spaces to be a sequential I-convergence ...
Renukadevi V., Vijayashanthi P.
doaj