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1.
Linearkombinationen von iterierten Bernsteinoperatoren   总被引:1,自引:0,他引:1  
The Bernstein polynomials Bn(f) approximate every function f which is continuous on [0, 1] uniformly on [0, 1]. Also the derivatives of the Bernstein polynomials approach the derivatives of the function f uniformly on [0, 1], if f has continuous derivatives. In this paper we shall introduce polynomial operators, namely linear combinations of iterates of Bernstein operators, which have the same properties but, under definite conditions, approximate f more closely than the Bernstein operators.  相似文献   

2.
In this paper, we improve the generalized Bernstein basis functions introduced by Han, et al. The new basis functions not only inherit the most properties of the classical Bernstein basis functions, but also reserve the shape parameters that are similar to the shape parameters of the generalized Bernstein basis functions. The degree elevation algorithm and the conversion formulae between the new basis functions and the classical Bernstein basis functions are obtained. Also the new Q-Bézier curve and surface...  相似文献   

3.
Extended Bernstein prior via reinforced urn processes   总被引:1,自引:0,他引:1  
A reinforced urn process, which induces a prior on the space of mixtures of Bernstein distributions is introduced. A nonparametric Bayesian model based on this prior is presented: the elicitation is treated and some connections with Dirichlet mixtures are given. In the last part of the article, an MCMC algorithm to compute the predictive distribution is discussed.  相似文献   

4.
主要介绍对称Bernstein Copula的一些性质及其应用.它除了具有Copula函数的基本性质外,还有其特殊性质,以定理的形式给出并加以证明.对称Bernstein Copula属于多参数Copula族,可以应用到很多领域,比如股票、汇率、证券等等.  相似文献   

5.
In this paper we give Markov Bernstein type inequalities for derivative of polynomials on some subsets of R. We define two different kinds of functions measuring the density of the sets considered, and in most cases we establish sharp inequalities for the Markov—Bernstein factor at the accumulation point of the set.  相似文献   

6.
The aim of the paper is to estimate the density functions or distribution functions measured by Wasserstein metric, a typical kind of statistical distances, which is usually required in the statistical learningBased on the classical Bernstein approximation, a scheme is presented.To get the error estimates of the scheme, the problem turns to estimating the L1 norm of the Bernstein approximation for monotone C-1functions, which was rarely discussed in the classical approximation theoryFinally, we get a probability estimate by the statistical distance.  相似文献   

7.
In this paper we give the estimates of the central moments for the limit q‐Bernstein operators. We introduce the higher order generalization of the limit q‐Bernstein operators and using the moment estimations study the approximation properties of these newly defined operators. It is shown that the higher order limit q‐Bernstein operators faster than the q‐Bernstein operators for the smooth functions defined on [0, 1]. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

8.
The numerical condition of the degree elevation operation on Bernstein polynomials is considered and it is shown that it does not change the condition of the polynomial. In particular, several condition numbers for univariate and bivariate Bernstein polynomials, and their degree elevated forms, are developed and it is shown that the condition numbers of the degree elevated polynomials are identically equal to their forms prior to degree elevation. Computational experiments that verify this theoretical result are presented. The results in this paper differ from those in [Comput. Aided Geom. Design 4 (1987) 191–216] and [Comput. Aided Geom. Design 5 (1988) 215–252], where it is claimed that degree elevation causes a reduction in the numerical condition of a Bernstein polynomial. It is shown, however, that there is an error in the derivation of this result.  相似文献   

9.
The purpose of this paper is twofold. First of all we characterize Bernstein algebras having a nilpotent kernel using idempotents of their multiplication algebras. Secondly, we describe some properties of Bernstein algebras which are preserved by isomorphisms of their multiplication algebras.  相似文献   

10.
In the present paper we study the orthogonal polynomials with respect to a measure which is the sum of a finite positive Borel measure on [0,2π] and a Bernstein–Szegö measure. We prove that the measure sum belongs to the Szegö class and we obtain several properties about the norms of the orthogonal polynomials, as well as, about the coefficients of the expression which relates the new orthogonal polynomials with the Bernstein–Szegö polynomials. When the Bernstein–Szegö measure corresponds to a polynomial of degree one, we give a nice explicit algebraic expression for the new orthogonal polynomials.  相似文献   

11.
We define and study a new family of univariate rational Bernstein operators. They are positive operators exact on linear polynomials. Moreover, like classical polynomial Bernstein operators, they enjoy the traditional shape preserving properties and they are total variation diminishing. Finally, for a specific class of denominators, some convergence results are proved, in particular a Voronovskaja theorem, and some error bounds are given.  相似文献   

12.
In this paper, the order of simultaneous approximation and Voronovskaja-type theorems with quantitative estimate for complex Bernstein–Durrmeyer-type polynomials attached to analytic functions on compact disks are obtained. Our results show that extension of the complex Bernstein–Durrmeyer-type polynomials from real intervals to compact disks in the complex plane extends approximation properties.  相似文献   

13.
A multidimensional generalization of the class of Bernstein functions is introduced and the properties of functions belonging to this class are studied. In particular, a new proof of the integral representation of Bernstein functions of several variables is given. Examples are considered.  相似文献   

14.
We show that the Bernstein polynomial basis on a given interval is ``optimally stable,' in the sense that no other nonnegative basis yields systematically smaller condition numbers for the values or roots of arbitrary polynomials on that interval. This result follows from a partial ordering of the set of all nonnegative bases that is induced by nonnegative basis transformations. We further show, by means of some low--degree examples, that the Bernstein form is not uniquely optimal in this respect. However, it is the only optimally stable basis whose elements have no roots on the interior of the chosen interval. These ideas are illustrated by comparing the stability properties of the power, Bernstein, and generalized Ball bases.

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15.
We construct Bernstein sets in ℝ having some additional algebraic properties. In particular, solving a problem of Kraszewski, Rałowski, Szczepaniak and Żeberski, we construct a Bernstein set which is a < c-covering and improve some other results of Rałowski, Szczepaniak and Żeberski on nonmeasurable sets.  相似文献   

16.
任意次的F-Bézier基统一了三角多项式空间上的C-Bézier基和双曲多项式空间上的H-Bézier基,我们证明这种基函数具有类似于基函数的优良性质,包括端点性质、对称性、升阶性质、线性无关性等,并且证明当形状参数趋于零时F-Bézier基收敛Bernstein基.  相似文献   

17.
The concern of this paper is to continue the investigation of convergence properties of nonlinear approximation operators, which are defined by Karsli. In details, the paper centers around Urysohn‐type nonlinear counterpart of the Bernstein operators. As a continuation of the study of Karsli, the present paper is devoted to obtain Voronovskaya‐type theorems for the Urysohn‐type nonlinear Bernstein operators.  相似文献   

18.
19.
In 1967 Durrmeyer introduced a modification of the Bernstein polynomials as a selfadjoint polynomial operator on L2[0,1] which proved to be an interesting and rich object of investigation. Incorporating Jacobi weights Berens and Xu obtained a more general class of operators, sharing all the advantages of Durrmeyer’s modification, and identified these operators as de la Vallée-Poussin means with respect to the associated Jacobi polynomial expansion. Nevertheless, all these modifications lack one important property of the Bernstein polynomials, namely the preservation of linear functions. To overcome this drawback a Bernstein-Durrmeyer operator with respect to a singular Jacobi weight will be introduced and investigated. For this purpose an orthogonal series expansion in terms generalized Jacobi polynomials and its de la Vallée-Poussin means will be considered. These Bernstein-Durrmeyer polynomials with respect to the singular weight combine all the nice properties of Bernstein-Durrmeyer polynomials with the preservation of linear functions, and are closely tied to classical Bernstein polynomials. Focusing not on the approximation behavior of the operators but on shape preserving properties, these operators we will prove them to converge monotonically decreasing, if and only if the underlying function is subharmonic with respect to the elliptic differential operator associated to the Bernstein as well as to these Bernstein-Durrmeyer polynomials. In addition to various generalizations of convexity, subharmonicity is one further shape property being preserved by these Bernstein-Durrmeyer polynomials. Finally, pointwise and global saturation results will be derived in a very elementary way.  相似文献   

20.
Sharp Riesz–Bernstein-type inequalities are proven for the derivatives of algebraic polynomials on general subsets of unit circle. The sharp Riesz–Bernstein constant involves the equilibrium density of the set in question.  相似文献   

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