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In this paper we study the right differentiability of a parametric infimum function over a parametric set defined by equality constraints. We present a new theorem with sufficient conditions for the right differentiability with respect to…

Optimization and Control · Mathematics 2023-06-22 Kevin Sturm

Let $\phi$ be a normalized convex function defined on open unit disk $\mathbb{D}$. For a unified class of normalized analytic functions which satisfy the second order differential subordination $f'(z)+ \alpha z f''(z) \prec \phi(z)$ for all…

Complex Variables · Mathematics 2020-12-29 Swati Anand , Naveen Kumar Jain , Sushil Kumar

In this paper, we introduce a subclass of close-to-convex functions defined in the open unit disk. We obtain the inclusion relationships, coefficient estimates and Fekete-Szego inequality. The results presented here would provide extension…

Complex Variables · Mathematics 2016-06-02 Yao Liang Chung , See Keong Lee , Maisarah Haji Mohd

Given an operator convex function $f(x)$, we obtain an operator-valued lower bound for $cf(x) + (1-c)f(y) - f(cx + (1-c)y)$, $c \in [0,1]$. The lower bound is expressed in terms of the matrix Bregman divergence. A similar inequality is…

Quantum Physics · Physics 2015-06-17 Isaac H. Kim

For a function $g\colon\{0,1\}^m\to\{0,1\}$, a function $f\colon \{0,1\}^n\to\{0,1\}$ is called a $g$-polymorphism if their actions commute: $f(g(\mathsf{row}_1(Z)),\ldots,g(\mathsf{row}_n(Z))) =…

Discrete Mathematics · Computer Science 2021-06-22 Gilad Chase , Yuval Filmus , Dor Minzer , Elchanan Mossel , Nitin Saurabh

A real-valued set function is (additively) approximately submodular if it satisfies the submodularity conditions with an additive error. Approximate submodularity arises in many settings, especially in machine learning, where the function…

Data Structures and Algorithms · Computer Science 2020-10-08 Flavio Chierichetti , Anirban Dasgupta , Ravi Kumar

Approximations of functions with finite data often do not respect certain "structural" properties of the functions. For example, if a given function is non-negative, a polynomial approximation of the function is not necessarily also…

Numerical Analysis · Mathematics 2020-08-20 Vidhi Zala , Robert M. Kirby , Akil Narayan

Given a continuous function $\phi$ defined on a domain $\Omega\subset\mathbb{R}^m\times\mathbb{R}^n$, we show that if a Pr\'ekopa-type result holds for $\phi+\psi$ for any non-negative convex function $\psi$ on $\Omega$, then $\phi$ must be…

Complex Variables · Mathematics 2025-01-22 Wang Xu , Hui Yang

Let $U\subseteq\mathbb{R}^d$ be open and convex. We prove that every (not necessarily Lipschitz or strongly) convex function $f:U\to\mathbb{R}$ can be approximated by real analytic convex functions, uniformly on all of $U$. We also show…

Differential Geometry · Mathematics 2014-10-24 Daniel Azagra

We introduce convex function intervals (CFIs): families of convex functions satisfying given level and slope constraints. CFIs naturally arise as constraint sets in economic design, including problems with type-dependent participation…

Theoretical Economics · Economics 2025-10-27 Victor Augias , Lina Uhe

In this paper we give an integral representation of an $n$-convex function $f$ in general case without additional assumptions on function $f$. We prove that any $n$-convex function can be represented as a sum of two $(n+1)$-times monotone…

Classical Analysis and ODEs · Mathematics 2010-08-17 Teresa Rajba

Here, we investigate the solutions to equation \[f(f(-x)+x)=f(-f(x))+f(x),\qquad x\in\mathbb{R}\] that are prescribed on the non-positive half-line. We will refer to this prescribed function as the generator of the corresponding solution.…

Classical Analysis and ODEs · Mathematics 2026-05-13 Tibor Kiss

Extending classical results on polytopal approximation of convex bodies, we derive asymptotic formulas for the weighted approximation of smooth convex functions by piecewise affine convex functions as the number of their facets tends to…

Optimization and Control · Mathematics 2025-10-01 Fernanda M. Baêta

Prox-regularity is a generalization of convexity that includes all C2, lower-C2, strongly amenable and primal-lower-nice functions. The study of prox-regular functions provides insight on a broad spectrum of important functions.…

Functional Analysis · Mathematics 2019-09-17 Warren Hare , Chayne Planiden

There exist two major subclasses in the class of superquadratic functions, one comprises concave and decreasing functions, while the other consists of convex and monotone increasing functions. Leveraging this distinction, we introduce…

Functional Analysis · Mathematics 2024-03-19 Mohsen Kian

Given a strictly positive measure, we characterize inner semicontinuous solid convex-valued mappings for which continuous functions which are selections almost everywhere are selections. This class contains continuous mappings as well as…

Optimization and Control · Mathematics 2013-08-23 Ari-Pekka Perkkiö

On the sets of $2\pi$-periodic functions $f$, which are defined with a help of $(\psi, \beta)$-integrals of the functions $\varphi$ from $L_{1}$, we establish Lebesgue-type inequalities, in which the uniform norms of deviations of Fourier…

Classical Analysis and ODEs · Mathematics 2023-01-06 Anatoly Serdyuk , Tetiana Stepaniuk

It is well-known that every convex function admits an affine support at every interior point of a domain. Convex functions of higher order (precisely of an odd order) have a similar property: they are supported by the polynomials of degree…

Functional Analysis · Mathematics 2008-07-28 Szymon Wasowicz

The present paper considers a problem of estimating a linear functional $\Phi=\int_{-\infty}^\infty \varphi(x) f(x)dx$ of an unknown deconvolution density $f$ on the basis of i.i.d. observations $Y_i = \theta_i + \xi_i$ where $\xi_i$ has a…

Statistics Theory · Mathematics 2015-05-19 Marianna Pensky

Here is one of the results obtained in this paper: Let $X, Y$ be two convex sets each in a real vector space, let $J:X\times Y\to {\bf R}$ be convex and without global minima in $X$ and concave in $Y$, and let $\Phi:X\to {\bf R}$ be…

Optimization and Control · Mathematics 2019-09-19 Biagio Ricceri