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351.
Several estimators for estimating the mean of a principal variable are proposed based on double sampling for stratification (DSS) and multivariate auxiliary information. The general properties of the proposed estimators are studied, search for optimum estimators is made and the proposed estimators are compared with the corresponding estimators based on unstratified double sampling (USDS). 相似文献
352.
Certain recurrence relations for the moments of different orders of the largest order statistic from a gamma distribution with shape parameter p are obtained. By using this it is shown that for obtaining the moment of any order of each order statistic of a sample of size n from the gamma distribution, one has to evaluate at most n-2 single integrals. 相似文献
353.
Gabriel Chandler Leif T. Johnson 《Journal of Statistical Computation and Simulation》2013,83(2):384-401
Tree-based methods similar to CART have recently been utilized for problems in which the main goal is to estimate some set of interest. It is often the case that the boundary of the true set is smooth in some sense, however tree-based estimates will not be smooth, as they will be a union of ‘boxes’. We propose a general methodology for smoothing such sets that allows for varying levels of smoothness on the boundary automatically. The method is similar to the idea underlying support vector machines, which is applying a computationally simple technique to data after a non-linear mapping to produce smooth estimates in the original space. In particular, we consider the problem of level-set estimation for regression functions and the dyadic tree-based method of Willett and Nowak [Minimax optimal level-set estimation, IEEE Trans. Image Process. 16 (2007), pp. 2965–2979]. 相似文献
354.
k-POD: A Method for k-Means Clustering of Missing Data 总被引:1,自引:0,他引:1
The k-means algorithm is often used in clustering applications but its usage requires a complete data matrix. Missing data, however, are common in many applications. Mainstream approaches to clustering missing data reduce the missing data problem to a complete data formulation through either deletion or imputation but these solutions may incur significant costs. Our k-POD method presents a simple extension of k-means clustering for missing data that works even when the missingness mechanism is unknown, when external information is unavailable, and when there is significant missingness in the data.[Received November 2014. Revised August 2015.] 相似文献
355.
356.
James T. Deffenbaugh 《Serials Review》2013,39(4):325-327
357.
358.
This paper considers the effects of the presence of eqmi-correlation between observations in a k-way factorial experiment, A technique to provide unbiased F-tests is also constructed. 相似文献
359.
T. W. Anderson 《Econometric Reviews》2013,32(1):41-47
In this paper we compare Bartlett-corrected, bootstrap, and fast double bootstrap tests on maximum likelihood estimates of cointegration parameters. The key result is that both the bootstrap and the Bartlett-corrected tests must be based on the unrestricted estimates of the cointegrating vectors: procedures based on the restricted estimates have almost no power. The small sample size bias of the asymptotic test appears so severe as to advise strongly against its use with the sample sizes commonly available; the fast double bootstrap test minimizes size bias, while the Bartlett-corrected test is somehow more powerful. 相似文献
360.
Susan P. Robbins PhD LCSW Associate Professor 《Smith College studies in social work》2013,83(1):88-91
From Diagnosis to Treatment in Child Psychiatry. Group for the Advancement of Psychiatry. (New York: Jason Aronson, Inc., 1974.) Psychotherapeutic Approaches to the Resistant Child. Dr. Richard Gardner. (New York: Jason Aronson, 1975.) 相似文献