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Abstract

The mean estimators with ratio depend on multiple auxiliary variables and unknown parameters in a finite population setting. We propose a new generalized approach with matrices for modeling the mutivariate mean estimators with two auxiliary variables. Our approach brings naturally a graphical analysis for comparing mean estimators.  相似文献   
3.
中国货币供给的内生性与货币政策分析   总被引:2,自引:0,他引:2  
从我国经济的短缺、过剩或转轨形态来看 ,我国的货币供给呈现很强的内生性 ,因此 ,货币政策应采取需求性的货币调控模式。相应地 ,货币政策的中介指标应选择利率而不是单纯的货币供应量。同时 ,利率改革的方向也不能单纯地瞄准完全的市场化利率体系 ,而应该是建立一种对利率进行间接调控的利率体系  相似文献   
4.
Summary: The H–family of distributions or H–distributions, introduced by Tukey (1960; 1977), are generated by a single transformation of the standard normal distribution and allow for leptokurtosis represented by the parameter h. Alternatively, Haynes et al. (1997) generated leptokurtic distributions by applying the K–transformation to the normal distribution. In this study we propose a third transformation, the so–called J–transformation, and derive some properties of this transformation. Moreover, so-called elongation generating functions (EGFs) are introduced. By means of EGFs we are able to visualize the strength of tail elongation and to construct new transformations. Finally, we compare the three transformations towards their goodness–of–fit in the context of financial return data.  相似文献   
5.
提出了变质量系统的相对论性万有D’Alembert原理,构造了相对论性广义动能函数,建立了变质量任意阶非线性非完整系统在准坐标下和广义坐标下的相对论性广义Mar-Millan型方程,并得到厂相应的型方程  相似文献   
6.
介绍了串联冰蓄冷系统设计中泵能耗的3种节能方法:串联泵,变频泵和制冷机旁通,通过对某工程实例的模拟计算,对比分析了这3种方式的节能效果,提出了有效的节能方式。  相似文献   
7.
WEIGHTED SUMS OF NEGATIVELY ASSOCIATED RANDOM VARIABLES   总被引:2,自引:0,他引:2  
In this paper, we establish strong laws for weighted sums of negatively associated (NA) random variables which have a higher‐order moment condition. Some results of Bai Z.D. & Cheng P.E. (2000) [Marcinkiewicz strong laws for linear statistics. Statist. and Probab. Lett. 43, 105–112,] and Sung S.K. (2001) [Strong laws for weighted sums of i.i.d. random variables, Statist. and Probab. Lett. 52, 413–419] are sharpened and extended from the independent identically distributed case to the NA setting. Also, one of the results of Li D.L. et al. (1995) [Complete convergence and almost sure convergence of weighted sums of random variables. J. Theoret. Probab. 8, 49–76,] is complemented and extended.  相似文献   
8.
一类二阶变系数微分方程的解   总被引:2,自引:0,他引:2  
通过变量变换 ,将变系数线性常微分方程化为常系数线性常微分方程 ,再利用常数变易法给出了一类二阶变系数非齐线性微分方程的通解。  相似文献   
9.
IntroductionCulturegivesanindividualananchoringpoint,ani dentity ,aswellascodesofconduct (MichaelR ,Iikka ,andMichaelH 2 0 0 2 :33) .Ofmorethan 16 0definitionsofculture (AlfredandClyde 1985 :11) ,mostagreeonsomebasicprinciples ,butthereisalotofvariationonthedetails .Cultureisalsomultidimensional ,consistingofanumberofcommonelementsthatareinterdependent.Thedifferencesinculturehaveanimportantimpactonmanyaspectsofamultinationalcompany’sactivity .Thispaperwillmainlydiscusstheeffectofsomeofthe…  相似文献   
10.
The sampling designs dependent on sample moments of auxiliary variables are well known. Lahiri (Bull Int Stat Inst 33:133–140, 1951) considered a sampling design proportionate to a sample mean of an auxiliary variable. Sing and Srivastava (Biometrika 67(1):205–209, 1980) proposed the sampling design proportionate to a sample variance while Wywiał (J Indian Stat Assoc 37:73–87, 1999) a sampling design proportionate to a sample generalized variance of auxiliary variables. Some other sampling designs dependent on moments of an auxiliary variable were considered e.g. in Wywiał (Some contributions to multivariate methods in, survey sampling. Katowice University of Economics, Katowice, 2003a); Stat Transit 4(5):779–798, 2000) where accuracy of some sampling strategies were compared, too.These sampling designs cannot be useful in the case when there are some censored observations of the auxiliary variable. Moreover, they can be much too sensitive to outliers observations. In these cases the sampling design proportionate to the order statistic of an auxiliary variable can be more useful. That is why such an unequal probability sampling design is proposed here. Its particular cases as well as its conditional version are considered, too. The sampling scheme implementing this sampling design is proposed. The inclusion probabilities of the first and second orders were evaluated. The well known Horvitz–Thompson estimator is taken into account. A ratio estimator dependent on an order statistic is constructed. It is similar to the well known ratio estimator based on the population and sample means. Moreover, it is an unbiased estimator of the population mean when the sample is drawn according to the proposed sampling design dependent on the appropriate order statistic.  相似文献   
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