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121.
We expand upon the known results on sharp linear Fourier methods of approximation where the approximation is the best in terms of both rate and constant among all polynomial procedures of approximation. So far these results have been studied due to their mathematical beauty rather than their practical importance. In this paper we show that they are the core mathematics underlying best statistical methods of solving noisy ill-posed problems. In particular, we suggest a procedure for recovery of noisy blurred signals based on samples of small sizes where a traditional statistics concludes that the complexity of such a setting makes the problem not worthy of a further study. Thus, we present a problem where a combination of the classical approximation theory and statistics leads to interesting practical results. 相似文献
122.
Tuo Zhao Kathryn Roeder Han Liu 《Journal of computational and graphical statistics》2013,22(4):895-922
Many statistical methods gain robustness and flexibility by sacrificing convenient computational structures. In this article, we illustrate this fundamental tradeoff by studying a semiparametric graph estimation problem in high dimensions. We explain how novel computational techniques help to solve this type of problem. In particular, we propose a nonparanormal neighborhood pursuit algorithm to estimate high-dimensional semiparametric graphical models with theoretical guarantees. Moreover, we provide an alternative view to analyze the tradeoff between computational efficiency and statistical error under a smoothing optimization framework. Though this article focuses on the problem of graph estimation, the proposed methodology is widely applicable to other problems with similar structures. We also report thorough experimental results on text, stock, and genomic datasets. 相似文献
123.
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125.
陈茂海 《数学的实践与认识》2003,33(5):75-81
本文选用三位式伪随机序列作为输入 ,充分利用其激励信号的各种特性 ,辨识非线性系统 Wiener模型的线性子系统脉冲响应函数 ,对非线性增益环节 ,则由其奇数和偶数项多项式系数分别进行估计 .同时研究线性与非线性子系统辨识的统计特性 ,给出各部分参数估计的置信区间 . 相似文献
126.
G. Huber T.A. Vilgis 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,3(2):217-223
The adsorption of a single ideal polymer chain on energetically heterogeneous and rough surfaces is investigated using a variational
procedure introduced by Garel and Orland (Phys. Rev. B 55, 226 (1997)). The mean polymer size is calculated perpendicular and parallel to the surface and is compared to the Gaussian
conformation and to the results for polymers at flat and energetically homogeneous surfaces. The disorder-induced enhancement
of adsorption is confirmed and is shown to be much more significant for a heterogeneous interaction strength than for spatial
roughness. This difference also applies to the localization transition, where the polymer size becomes independent of the
chain length. The localization criterion can be quantified, depending on an effective interaction strength and the length
of the polymer chain.
Received: 29 October 1997 / Revised: 19 December 1997 / Accepted: 6 March 1998 相似文献
127.
设x1,x2,…xn(连续未知),Fn为经验分布函数,Hn(x)为随机加权经验分布函数,。xn1≤xn2≤…≤xnn为次序统计量.记以Fn取代σ2(J,F)中的F即得σ2(J,Fn). 相似文献
128.
SOME COMPARISONS BETWEEN GENERALIZED ORDER STATISTICS 总被引:1,自引:0,他引:1
Qiu Guoxin Wang Jinshan 《高校应用数学学报(英文版)》2007,22(3):325-333
Some stochastic comparisons of generalized order statistics under the right spread order,the location independent riskier order and the total time transform order are investigated in this paper.The underlying distributions and parameters on which generalized order statistics are based are also surveyed to obtain the conditions for increasing the expectations of spacings between the first two generalized order statistics and between the last two generalized order statistics. 相似文献
129.
在运用数理统计方法分析实际数据的基础上,结合国内外的已有研究结果,初步认为在自行车流量小的情况下,泊松分布比较适用于描述自行车到达量的统计分布;而当自行车流量很大时,负二项分布比较适合描述一定条件下的自行车到达量的统计分布.考虑到自行车到达分布的复杂性,文中借鉴知识推理的一些概念和方法,非精确地描述了自行车到达分布规律. 相似文献
130.
This work establishes an asymptotic bound on the characteristic function of signed linear serial rank statistics. The result is obtained under rather general conditions including the important case of van der Waerden scores. It generalizes the result of Seoh (1983, Ph.D. Thesis, Department of Mathematics, Indiana University) and constitutes an essential step to the elaboration of Berry-Esséen's bounds and the establishment of Edgeworth expansions. These statistics constitute a natural tool for testing the hypothesis of white noise with a symmetrical (unspecified) distribution in comparison to other alternative hypothesis of serial dependence. 相似文献