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1.
We carried out an empirical performance study of outlier detection procedures for Weibull or extreme-value distributions using a mixture model in which a known number of randomly chosen observations are contaminated. Procedures studied were: L(L') based on leaps (differences of adjacent observations divided by expectation), V, Q and W (Mann, 1982), R1(R'1), R2(R'2), R3(R'3) (Dixon, 1950) and G(G') (Grubbs, 1950). Percentage points for statistics L(L'), R1(R1), R2(R'2), R3(R'3) and G(G') were computed empirically for the extreme-value distribution and are tabulated. The procedures L(L') (or equivalently in power V) performed best, with few exceptions, for the contaminated model tested. The Grubb statistic G' performed well in testing for lower outliers. Mann's W , which was best for the labeled slippage was substantially poorer than the others for the mixture model. Dixon's R1 (R1) is recommended as a generally useful test for sample sizes in the range investigated (n=5,20)  相似文献   

2.
In the present paper the behavior of solutions of the mixed Zaremba's problem in the neighborhood of a boundary point and at infinity is studied. In part I of this paper[4] the concept of Wiener's generalized solution of Zaremba's problem was introduced and the so called Growth Lemma for the class of domains, satisfying isoperimetric condition, was proven. In part II regularity criterion for joining points of Neumann's and Dirichlet's boundary conditions is formulated. Generalized solution in unlimited domains as a limit of Zaremba's problem's solutions in a sequence of limited domains is introduced and a regularity condition allowed to obtain an analogue of Phragmen-Lindeloeff theorem for the solutions of Zaremba's problem. Main results of the present paper are formulated in terms of divergence of Wiener's type series.  相似文献   

3.
张攀  张量  宋卫东 《数学杂志》2016,36(3):445-457
本文研究了拟常曲率黎曼流形中子流形的Chen不等式.利用代数技巧,建立了Chen广义不等式、Chen-Ricci不等式和关于卷积函数和平均曲率平方的不等式,推广了Özgür和Chen的一些结果.  相似文献   

4.
吴栩 《数学杂志》2014,34(5):941-946
本文研究了一类可数点集的盒维数的计算问题.通过构造双Lipschitz映射,把原可数点集的盒维数的求解问题转化为求解一类相对简单的可数点集的盒维数.获得了两个单调的可数点集在具有同阶间隔时具有相同的上盒维数和下盒维数的结论.该结论为计算一类可数点集的盒维数提供了方便.  相似文献   

5.
We present here, in compact form, the necessary and sufficient conditions for linearization of third-order ordinary differential equations y'''=f (x,y,y', y'') with maximal symmetry group via point transformation. A simple procedure to construct the point transformation using the isomorphism of the symmetry subalgebra sl(2, ?) is also presented. This subalgebra is the semi-simple part of the Levi-Decomposition for the 7-dimensional symmetry algebra.  相似文献   

6.
In this paper, we investigate the existence of solutions of a fully nonlinear fourth-order differential equation $$x^{(4)}=f(t,x,x',x'',x'''),\quad t\in [0,1]$$ with one of the following sets of boundary value conditions; $$x'(0)=x(1)=a_{0}x''(0)-b_{0}x'''(0)=a_{1}x''(1)+b_{1}x'''(1)=0,$$ $$x(0)=x'(1)=a_{0}x''(0)-b_{0}x'''(0)=a_{1}x''(1)+b_{1}x'''(1)=0.$$ By using the Leray-Schauder degree theory, the existence of solutions for the above boundary value problems are obtained. Meanwhile, as an application of our results, an example is given.  相似文献   

7.
Halley's method is a higher order iteration method for the solution of nonlinear systems of equations. Unlike Newton's method, which converges quadratically in the vicinity of the solution, Halley's method can exhibit a cubic order of convergence. The equations of Halley's method for multiple dimensions are derived using Padé approximants and inverse one-point interpolation, as proposed by Cuyt. The investigation of the performance of Halley's method concentrates on eight-node volume elements for nonlinear deformations using Staint Venant-Kirchhoff's constitutive law, as well as a geometric linear theory of von Mises plasticity. The comparison with Newton's method reveals the sensibility of Halley's method, in view of the radius of attraction but also demonstrates the advantages of Halley's method considering simulation costs and the order of convergence. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

8.
We know that, in general, an algebra satisfying an Engel's condition is a nilalgebra. But an Engel's condition don't implies necessarily the nilpotency of the algebra. In this paper we show that every Bernstein algebra satisfying the second or the third Engel's condition is genetic, that is, the kernel of his weight fonction is nilpotent. This is also the case for a Bernstein algebra satisfying the second weak Engel's condition.

On sait que, en général, toute algèbre vérifiant une condition d'Engel est une nilalgèbre. Cependant, une condition d'Engel n'entraîne pas nécessairement la nilpotence de l'algèbre. Nous montrons, dans ce papier, que taute algèbre de Bernstein vérifiant la deuxième ou la troisième condition d'Engel est génétique, c'est-à-dire, le noyau de sa pondération est nilpotent. C'est aussi le cas pour la deuxième condition faible d'Engel.  相似文献   

9.
This paper reports an inquiry into assessment items classed as 'extended pieces of work' in Applicable Mathematics, in Western Australia. The principal purpose was to identify opportunities for graphics calculator use in 'extended pieces' implemented in schools. Ownership of the technology is widespread because it is mandated for the Applicable Mathematics tertiary entrance examination, which students sit at the end of the Year 12 course. Twenty-one of the twenty-eight pieces that were collected allowed for calculator use and, frequently, choosing to use the technology would have advantaged students, for instance, in supporting conjecture. Practical applications that would not be feasible to solve without the technology were included. Regression analysis and the random number generator were utilized. Overall, availability of the technology has widened the scope of approaches in 'extended pieces of work' in potentially valuable ways. Issues are how conjectures were elicited and calls for 'black box' use of the calculator.  相似文献   

10.
We report a study of children's probability conceptions and misconceptions using a diagnostic instrument developed from the literature on the representativeness heuristic. Rasch measurement methodology was used to develop the 13-item open response instrument with a sample (n=116) of 12-15 year olds. The result is that a hierarchy of responses at two levels is confirmed for this sample, and a third level is hypothesised. Each level is characterised by the ability to overcome typical 'representativeness' effects, namely 'recency', 'random-similarity' (at level 1), 'base-rate frequency' and 'sample size' (at level 2-3). The validity of our interpretations was tested and some anomalies were identified through clinical interviews with children making the errors (n=8). Another Rasch ability measure, which we named the 'representativeness tendency', was constructed from 11 multiple-choice errors.  相似文献   

11.
12.
在本文中, 我们得到了Type I McKay Distribution的Stein方程的通解. 我们证明了其Stein方程的有界解存在且唯一. 进一步的我们研究了其应的有界解的一些性质. 这对用Stein方法取研究Type I McKay分布的逼近可能会有一些作用.  相似文献   

13.
In this paper, we study Ito''s 5th-order mKdV equation with the aid of symbolic computation system and by qualitative analysis of planar dynamical systems. We show that the corresponding higher-order ordinary differential equation of Ito''s 5th-order mKdV equation, for some particular values of the parameter, possesses some sub-manifolds defined by planar dynamical systems. Some solitary wave solutions, kink and periodic wave solutions of the Ito''s 5th-order mKdV equation for these particular values of the parameter are obtained by studying the bifurcation and solutions of the corresponding planar dynamical systems.  相似文献   

14.
We give a simple proof and a multivariable generalization of an identity due to E. Alkan concerning a weighted average of the Ramanujan sums. We deduce identities for other weighted averages of the Ramanujan sums with weights concerning logarithms, values of arithmetic functions for gcd’s, the Gamma function, the Bernoulli polynomials, and binomial coefficients.  相似文献   

15.
利用DEA方法计算出2009-2013年5年间全国31个省份财政民生支出资金配置的综合技术效率、纯技术效率、规模效率三种效率值,分析出各省份政府财政民生支出所处规模报酬阶段.结果显示:大部分省份的政府财政民生支出DEA得分在0.9以上,说明虽然效率没有达到最优水平,但是总体来说效率水平还是比较高的.另外,各省市财政民生产出存在较大的差异,东部地区综合产出水平高于中西部地区,其中,西部地区效率最低,改进空间最大.  相似文献   

16.
We first note that Gentzen's proof-reduction for his consistency proof of PA can be directly interpreted as moves of Kirby-Paris' Hydra Game, which implies a direct independence proof of the game (Section 1 and Appendix). Buchholz's Hydra Game for labeled hydras is known to be much stronger than PA. However, we show that the one-dimensional version of Buchholz's Game can be exactly identified to Kirby-Paris' Game (which is two-dimensional but without labels), by a simple and natural interpretation (Section 2). Jervell proposed another type of a combinatorial game, by abstracting Gentzen's proof-reductions and showed that his game is independent of PA. We show (Section 3) that this Jervell's game is actually much stronger than PA, by showing that the critical ordinal of Jervell's game is φω (0) (while that of PA or of Kirby-Paris' Game is φ1 (0) = ?0) in the Veblen hierarchy of ordinals.  相似文献   

17.
本文主要研究了单边Calder\''{o}n-Zygmund奇异积分交换子的加权变差不等式,即建立了单边Calder\''{o}n-Zygmund奇异积分与Lipschitz函数生成的交换子的加权变差不等式, 同时,利用权的外推法得到了该交换子在Triebel-Lizorkin空间上的加权变差不等式.  相似文献   

18.
我们运用扰动方法证明了带有Minkowski平均算子非局部Neumann系统$$\begin{aligned}\begin{cases}\Big(r^{N-1}\frac{u''}{\sqrt{1-u''^{2}}}\Big)''=r^{N-1}f(r, u),\\\ r\in(0, 1),\ \ \ u''(0)=0,\ \ \ u''(1)=\int_{0}^{1}u''(s)dg(s)\\\end{cases}\end{aligned}$$解的存在性, 其中$k, N\geq1$是整数, $f=(f_{1},f_{2},\ldots,f_{k}):[0, 1]\times\mathbb{R}^{k}\rightarrow\mathbb{R}^{k}$连续且$g:[0, 1]\rightarrow\mathbb{R}^{k}$是有界变差函数.  相似文献   

19.
A comparison by Wang and Xu between S. Samle's cost estimation for Newton's method and that of the author's for Kuhn's algorithm, both aiming at the zero finding of complex polynomials, showed improvements the advantage of the latter in finding zeros and approximate zeros. In this paper, important on the above work are made. Furthermore, a probabilistic estimation of the monotonicity of Kuhn's algorithm is obtained.  相似文献   

20.
设2≤h≤3,l0,k≥0是整数,C_h(l,k)是由h-边连通简单图组成的集合,图G∈C_h(l,k)当且仅当对图G的任意一个二边割或三边割X,图G-X的每个分支都至少有︱V(G)-k︱/l个点.设e=u_1v_1和e'=u_2v_2是图G的两条边.若e≠e',G(e,e')是将图G中的边e=u_1v_1和e'=u_2v_2分别用路u_1v_ev_1和u_2v_e'v_2替换得到的图(其中,v_e,v_e'是不在V(G)中的两个新的点).若e=e',G(e,e')是将图G中的边e=u_1v_1用路u_1v_ev_1替换得到的图,也记作G(e).若对任意的e,e'∈E(G),G(e,e')都有支撑(v_e,v_e')迹,则称图G是强支撑可迹的.作者证明了,若图G∈C_2(4,k)且|V(G)|5k,则要么图G是强支撑可迹图,要么存在e,e'∈E(G),使得G(e,e')可以收缩成一个有限图类F中的图.当k=4时,F被完全确定了.  相似文献   

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