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851.
M. D. Martínez-Miranda M. Rueda-Garcia A. Arcos-Cebrián Y. Román-Montoya S. Gonzalez-Aguilera 《Computational Statistics》2005,20(3):385-399
This paper deals with the estimation, under sampling in two successive occasions, of a finite population quantile. For this
sampling design a class of estimators is proposed whose the ratio and difference estimators are particular cases. Asymptotic
variance formulae are derived for the proposed estimators, and the optimal matching fraction is discussed. Comparisons are
made with existing estimators in a simulation study using a natural population. 相似文献
852.
采样数据的增加究竟有多少相应的有效Fisher信息增益,这是测量数据处理、图像数据融合等应用领域中关心的问题.以(共轭)正态分布为基础,利用统计推断理论,导出一定相关性下样本数据的增加与统计信息(Fisher信息)增益之间的关系,并经一维航天测量数据和二维图像超分辨仿真算例验证. 相似文献
853.
Bernd A. Berg 《Journal of statistical physics》1996,82(1-2):323-342
The problem of calculating multicanonical parameters recursively is discussed. I describe in detail a computational implementation which has worked reasonably well in practice. 相似文献
854.
一种风险型决策的决策方法 总被引:1,自引:0,他引:1
本文阐明了方案益损值和自然状态概率无准确估计的风险型决策问题的决策方法。证明了在期望值决策准则下,用等概率分层随机抽样得到的方案收益期望值的均值,与用简单随机抽样得到的相同。用正交表进行分层随机抽样,得到方案收益期望值服从正态分布的均值和方差。再根据统计推断理论对方案作出选择,并给出决策的风险估计。 相似文献
855.
在几种常见的抽样方案下的事后分层 总被引:1,自引:0,他引:1
本文给出系统抽样,放回不等概率抽样及二阶不等概率抽样情况下总体均值的事后分层估计,估计量的方差和它的无偏估计。 相似文献
856.
The paper studies the optimal sequential sampling policy of the partitioned random search (PRS) and its approximation. The PRS is a recently proposed approach for function optimization. It takes explicitly into consideration computation time or cost, assuming that there exist both a cost for each function evaluation and a finite total computation time constraint. It is also motivated at improving efficiency of the widely used crude random search. In particular, the PRS considers partitioning the search region of an objective function into K subregions and employing an independent and identically distributed random sampling scheme for each of K subregions. A sampling policy decides when to terminate the sampling process or which subregion to be sampled next. 相似文献
857.
Michał Ramsza 《International Journal of Game Theory》2005,33(4):515-521
The idea of procedurally rational players was introduced in [4]. Among other procedures, the sampling procedure was proposed.
The resulting equilibrium was called a sampling equilibrium. Evolutionary approach to the notion of a sampling equilibrium was developed in [7], where some instability results were
proved. Using the concept of first-order stochastic dominance, we introduce the notion of a superior strategy and prove a
stability result.
The paper was supported by the Polish Government Grant No. KBN 5P03A 025 20. Author wishes to thank an anonymous referee for
useful comments and suggestions. 相似文献
858.
Guo Hua Zou 《数学学报(英文版)》2002,18(1):37-46
This paper considers the admissibility of the estimators for finite population when the parameter space is restricted. We
obtain all admissible linear estimators of an arbitrary linear function of characteristic values of a finite population in
the class of linear estimators under the criterion of the expectation of mean squared error.
Received February 12, 1999, Revised October 8, 1999, Accepted January 14, 2000 相似文献
859.
Boundary Crossing Probabilities for Scan Statistics and Their Applications to Change-Point Detection
This paper gives a brief review of recent developments in change-point detection and in the associated boundary crossing problems. Making use of saddlepoint approximations for Markov random walks, we give further extensions of a basic result on boundary crossing probabilities, leading to detection procedures that are not too de-manding in computational and memory requirements and yet are nearly optimal under several performance criteria. 相似文献
860.
Analytical methods for arsine, silane and dichlorosilane by adsorption sampling and elemental analysis with graphite furnace AA were studied to establish convenient methods for atmospheric contamination surveys. This study included the following five items: (1) primary selection of adsorbents applicable to adsorption sampling; (2) examination of the adsorption capacities of the adsorbents for the gases; (3) improvement of the adsorbents by chemical modification; (4) desorption of the gases adsorbed on the adsorbents with solvents; and (5) quantitative analysis of arsenic and silicon in the solutions. Experimental results showed that active carbon made from synthetic thermosetting resin beads contained no aresenic and little silicon as impurities. This active carbon by itself was proved to adsorb arsine and dichlorosilane, but not silane. Impregnation with sodium hydroxide of the active carbon improved the adsorption capacity for all three gases. Refined silica gel, free from arsenic contamination, did not adsorb arsine by itself but potassium permanganate impregnation produced an adsorption capacity for arsine. The adsorbed arsine on the active carbon was desorbed into a hot dilute nitric acid solution with high efficiency (over 90%), but arsine adsorbed on sodium hydroxide impregnated active carbon or on potassium permanganate impregnated silica gel was dissolved into various solutions only at lower efficiencies. Silane adsorbed on sodium hydroxide-impregnated active carbon was desorbed with hot water with an efficiency higher than 90%. Dichlorosilane adsorbed on the active carbon with or without sodium hydroxide impregnation was desorbed with a nitric acid solution with efficiency of 85%. The lower determination limit for arsine able to discriminate from background interference of arsenie was 0.005 ppm, and those for silane and dichlorosilane were each 0.05 ppm for 3-dm3 air samples. 相似文献