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61.
In this article we deal with the problem of stability of the conclusions from principal components analysis over repeated
samples. We define a measure of stability for each component and investigate some of the measures properties. We then obtain
the maximum likelihood estimators (MLEs) of the measures, and derive their joint limiting distributions. The MLEs of the measures
turn out to be asymptotically unbiased and jointly have the multivariate normal distribution. Modified estimators are also
found to reduce the amount of bias in the MLEs. To facilitate interpretation of the measures we define stability confidence
level as coverage probability, and associate with each measure a stability confidence level to describe the measure in terms
of probability. Finally, we investigate the stability of the components via a simulation study and compare the performance
of the MLEs and the modified estimators in terms of bias and precision.
This work was sponsored by a grant from the Office of Vice-President for Research at Kuwait University under project number
SS049. 相似文献
62.
Manoj Chacko P. Yageen Thomas 《Annals of the Institute of Statistical Mathematics》2008,60(2):301-318
Ranked set sampling is applicable whenever ranking of a set of sampling units can be done easily by a judgement method or
based on the measurement of an auxiliary variable on the units selected. In this work, we consider ranked set sampling, in
which ranking of units are done based on measurements made on an easily and exactly measurable auxiliary variable X which is correlated with the study variable Y. We then estimate the mean of the study variate Y by the BLUE based on the measurements made on the units of the ranked set sampling regarding the study variable Y, when (X ,Y) follows a Morgenstern type bivariate exponential distribution. We then consider unbalanced multistage ranked set sampling
and estimate the mean of the study variate Y by the BLUE based on the observations made on the units of multistage ranked set sample regarding the study variable Y. Efficiency comparison is also made on all estimators considered in this work. 相似文献
63.
本文通过将使用时间在可能发生故障的时刻划分成时间区间,对修如旧模型下的多部件系统,在修理延迟条件下,对各类故障在同一时间区间里相容的条件下导出了任意给定时刻设备的可用度函数,并对文[3]中的算法做了改进,得到了更精确更合理的结果 相似文献
64.
This paper proposes bootstrap tests for the presence of unit roots in a seasonal autoregressive model. The asymptotic validity of the proposed bootstrap scheme is established, and Monte Carlo experiments are used to investigate the small-sample performance of the tests. 相似文献
65.
A LAW OF ITERATED LOGARITHM FOR THE MLE IN A RANDOM CENSORING MODEL WITH INCOMPLETE INFORMATION 总被引:1,自引:0,他引:1
In this article, a law of iterated logarithm for the maximum likelihood estimator in a random censoring model with incomplete information under certain regular conditions is obtained. 相似文献
66.
Ze-shui Xu 《佛山科学技术学院》2009,1(1):79-89
An intuitionistic preference relation is a powerful means to express decision makers’information of intuitionistic preference
over criteria in the process of multi-criteria decision making. In this paper, we first define the concept of its consistence
and give the equivalent interval fuzzy preference relation of it. Then we develop a method for estimating criteria weights
from it, and then extend the method to accommodate group decision making based on them And finally, we use some numerical
examples to illustrate the feasibility and validity of the developed method. 相似文献
67.
In this paper, a theorem on the moderate deviation principle for random arrays under m-dependence with unbounded m is established. This partially extends the results of Chen (Stat. Probab. Lett. 35:123–134, 1997). As an application, the moderate deviation principle for the truncation estimator of the variance in the analysis of time
series is obtained.
相似文献
68.
拟似然非线性模型中最大拟似然估计的强相合性 总被引:2,自引:0,他引:2
This paper proposes some regularity conditions. On the basis of the proposed regularity conditions, we show the strong consistency of maximum quasi-likelihood estimation (MQLE) in quasi-likelihood nonlinear models (QLNM). Our results may be regarded as a further generalization of the relevant results in Ref. [4]. 相似文献
69.
Yutaka Kano 《Annals of the Institute of Statistical Mathematics》1986,38(1):57-68
Summary This paper is concerned with the consistency of estimators in a single common factor analysis model when the dimension of
the observed vector is not fixed. In the model several conditions on the sample sizen and the dimensionp are established for the least squares estimator (L.S.E.) to be consistent. Under some assumptions,p/n→0 is a necessary and sufficient condition that the L.S.E. converges in probability to the true value. A sufficient condition
for almost sure convergence is also given. 相似文献
70.
§ 1.Introduction and Notations In this paper,for any given matrices A and B,A B denotes the Kronecker productof A and B,A is a vector formed by stacking the columns of A under each other,μ(A)is a space generated by the columns of A,and PA=A(A′A) - A′. Fourthmore,if A andB are square matrices,then A>B and A≥ B mean that A-B is a symmetrical positiveand nonnegative matrix,respectively,andλi(A) is the i-th largest eigenvalue of A. Consider general multivariate linear modelY … 相似文献