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971.
972.
In this article, we obtain expressions for the pdf of a single concomitant of order statistic and the joint pdf of a pair of concomitants of order statistics of independent non identically distributed random variables. Using these expressions, we find the means, variances and covariances of order statistics arising from independent non identically distributed bivariate Pareto distributions. A method of estimation of a common parameter involved in several bivariate Pareto distributions using concomitants of order statistics is also discussed.  相似文献   
973.
We sample m (m ≥ 1) i.i.d. Pareto random variables with the density function x ?2 (x ≥ 1) and establish two large deviations for the partial sums. In addition, the maxima of sums of the two-tailed Pareto random variables is discussed and some asymptotical forms are obtained also.  相似文献   
974.
In this article, we establish a new complete convergence theorem for weighted sums of negatively dependent random variables. As corollaries, many results on the almost sure convergence and complete convergence for weighted sums of negatively dependent random variables are obtained. In particular, the results of Jing and Liang (2008 Jing, B.Y., Liang, H.Y. (2008). Strong limit theorems for weighted sums of negatively associated random variables. J. Theor. Probab. 21:890909.[Crossref], [Web of Science ®] [Google Scholar]), Sung (2012 Sung, S.H. (2012). Complete convergence for weighted sums of negatively dependent random variables. Stat. Pap. 53:7382.[Crossref], [Web of Science ®] [Google Scholar]), and Wu (2010) can be obtained.  相似文献   
975.
This paper deals with estimation of population median in simple and stratified random samplings by using auxiliary information. Auxiliary information is rarely used in estimating population median, although there have been many studies to estimate population mean using auxiliary information. In this study, we suggest some estimators using auxiliary information such as mode and range of an auxiliary variable and correlation coefficient. We also expand these estimators to stratified random sampling for combined and separate estimators. We obtain mean square error equations for all proposed estimators and find theoretical conditions. These conditions are also supported by using numerical examples.  相似文献   
976.
In this article, we consider the problem of best linear unbiased estimation and best linear invariant estimation of the common scale parameter of several symmetric distributions using some functions of spacings of all observations taken from individual samples. We also proved a sufficient condition for the non negativity of the common scale estimator obtained by the above method. Furthermore, we obtained necessary and sufficient conditions for the derived estimators to be constant multiple of the sum of first and last spacings of the pooled sample.  相似文献   
977.
The scope of the term “Mining Geostatistics” is defined in the context of a brief historical review of the topic. Assumptions andtools adapted from probability theory are applied first to linear estimation problems leading to the iging” estimator and then shown capable of extension to non- ationary and non-linear situa­tions, in which conditional simulation, conditional distributions and “disjunctive Kriging” become applicable. Directions for further research work are indicated regarding variogram identification and modelling of random functions where stationarity or linearity may not hold. The brief review suggests that the mutual benefits of practice and theory will continue to develop.  相似文献   
978.
For testing goodness-of-fit in a k cell multinomial distribution having very small frequencies, the usual chi-square approximation to the upper tail of the likelihood ratio statistic, G2 is not satisfactory. A new adjustment to G2 is determined on the basis of analytical investigation in terms of asymptotic bias and variance of the adjusted G2 A Monte Carlo simulation is performed for several one-way tables to assess the adjustment of G2 in order to obtain a closer approximation to the nomial level of significance.  相似文献   
979.
ABSTRACT

In this paper, we study the complete convergence and complete moment convergence for negatively orthant-dependent random variables. Especially, we obtain the Hsu–Robbins-type theorem for negatively orthant-dependent random variables. Our results generalize the corresponding ones for independent random variables.  相似文献   
980.
This paper deals with the estimation of "the fraction of variance expiained" in one-way classification. A comparative study of two estimators for model II (random effects) is made by computing approximately their biases and mean-square errors in the balanced case. A similar study is made for model I (fixed effects) where we study one estimator and give asymptotic formulae for its bias and mean-square error.  相似文献   
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