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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.
Herein, we propose a data-driven test that assesses the lack of fit of nonlinear regression models. The comparison of local linear kernel and parametric fits is the basis of this test, and specific boundary-corrected kernels are not needed at the boundary when local linear fitting is used. Under the parametric null model, the asymptotically optimal bandwidth can be used for bandwidth selection. This selection method leads to the data-driven test that has a limiting normal distribution under the null hypothesis and is consistent against any fixed alternative. The finite-sample property of the proposed data-driven test is illustrated, and the power of the test is compared with that of some existing tests via simulation studies. We illustrate the practicality of the proposed test by using two data sets.  相似文献   
4.
Many applications of nonparametric tests based on curve estimation involve selecting a smoothing parameter. The author proposes an adaptive test that combines several generalized likelihood ratio tests in order to get power performance nearly equal to whichever of the component tests is best. She derives the asymptotic joint distribution of the component tests and that of the proposed test under the null hypothesis. She also develops a simple method of selecting the smoothing parameters for the proposed test and presents two approximate methods for obtaining its P‐value. Finally, she evaluates the proposed test through simulations and illustrates its application to a set of real data.  相似文献   
5.
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   
6.
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   
7.
福建宁德畲族(聚居区)文化遗产保护与利用的调查报告   总被引:3,自引:0,他引:3  
福建宁德畲族文化作为中华畲族文化的主源头之一,在团结与凝聚当地和国内外的畲族同胞,增进人们对畲族历史文化和现实了解方面发挥了不可替代的纽带作用,它与聚居区内景色秀丽的山水风光相映成趣,具有潜力巨大的旅游价值与产业价值。但近期以来,该地畲族传统文化也面临着逐渐失传的现实危机。抓紧实施抢救与发展畲族文化遗产系统工程的各项具体工作,对于继承畲族优秀传统文化,促进地方自然生态、文化生态与经济的和谐发展具有重要的意义。  相似文献   
8.
To prepare for the complexities of family formation, 78 prospective adoptive parents participated in Pre-Adopt, a psychosocial educational orientation program offered by one private nonprofit agency. The five-session curriculum included an overview of adoption policies and procedures, discussion of the child placement process, exploration of couples' adoption concerns and expectations about child characteristics, information about adoption laws and birth-parent/child searches, and examination of anticipatory fantasies about birth parents. Program evaluation yielded statistically significant and clinically meaningful findings about changes in emotional readiness to adopt, parenting knowledge, and satisfaction with group participation, adoption policies and agency practices. Practice implications are considered.  相似文献   
9.
市场调查:图书选题计划制定的关键   总被引:1,自引:0,他引:1  
加强市场调查对提高图书选题策划的预测准确性作用极大。市场导向和市场反馈,将直接有助于出版机构了解市场的饱和点、空白点、热点、增长点和萎缩点,正确判断图书市场的现状和未来走势,进而在制订选题计划时更为合理地进行因势利导和科学决策。  相似文献   
10.
For two-parameter exponential populations with the same scale parameter (known or unknown) comparisons are made between the location parameters. This is done by constructing confidence intervals, which can then be used for selection procedures. Comparisons are made with a control, and with the (unknown) “best” or “worst” population. Emphasis is laid on finding approximations to the confidence so that calculations are simple and tables are not necessary. (Since we consider unequal sample sizes, tables for exact values would need to be extensive.)  相似文献   
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