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81.
In this paper a method for the construction of a class of row-column designs with good statistical properties and high efficiency is presented. The class of designs produced is shown to exhibit balance, orthogonality and adjusted orthogonality. The efficiencies of these designs are investigated in detail, and they are shown to be very high, and possibly maximal in some cases. 相似文献
82.
We propose a method for the analysis of a spatial point pattern, which is assumed to arise as a set of observations from a spatial nonhomogeneous Poisson process. The spatial point pattern is observed in a bounded region, which, for most applications, is taken to be a rectangle in the space where the process is defined. The method is based on modeling a density function, defined on this bounded region, that is directly related with the intensity function of the Poisson process. We develop a flexible nonparametric mixture model for this density using a bivariate Beta distribution for the mixture kernel and a Dirichlet process prior for the mixing distribution. Using posterior simulation methods, we obtain full inference for the intensity function and any other functional of the process that might be of interest. We discuss applications to problems where inference for clustering in the spatial point pattern is of interest. Moreover, we consider applications of the methodology to extreme value analysis problems. We illustrate the modeling approach with three previously published data sets. Two of the data sets are from forestry and consist of locations of trees. The third data set consists of extremes from the Dow Jones index over a period of 1303 days. 相似文献
83.
运用以密度泛函理论为基础的相对论性离散变分方法(DV-Xα),模拟计算了完整的和含氧空位的钼酸钙(CaMoO_4)晶体的电子结构,得到了含有F、F~ 心的CaMoO_4晶体电子态密度分布以及它们可能产生的光学跃迁模式.计算结果表明,含F、F~ 心的CaMoO_4晶体的禁带宽度明显变窄,F、F~ 心的能级出现在禁带中,利用过渡态理论计算得到其向Mo的4 d轨道发生光学跃迁,跃迁能量值分别为1.93,2.03 eV.利用提拉法生长的CaMoO_4晶体呈现蓝色的本质原因是F、F~ 心在黄红区产生比较强的吸收. 相似文献
84.
The problem considered relates to large-scale sample surveys. A new estimator of population total for the characteristics that are poorly correlated with the selection probabilities has been developed for the PPSWR sampling scheme. The relative efficiency of the proposed estimator has been studied under a super-population model. A numerical investigation into the performance of the estimator has also been made. 相似文献
85.
W.Y. Tan 《Journal of statistical planning and inference》1985,11(3):329-340
Tiku's robust procedure for testing mean and variance from nonnormal universe is examined from the Bayesian viewpoint. The posterior distribution of the scale parameter is derived and then approximated by a Laguerre polynomial expansion while the posterior distribution of the location parameter is approximated by a linear combination of t-distributions. For the example with Darwin's data, the approximations appear to be extremely good. 相似文献
86.
Stefanie Biedermann Holger Dette Andrey Pepelyshev 《Journal of statistical planning and inference》2007
We investigate optimal designs for discriminating between exponential regression models of different complexity, which are widely used in the biological sciences; see, e.g., Landaw [1995. Robust sampling designs for compartmental models under large prior eigenvalue uncertainties. Math. Comput. Biomed. Appl. 181–187] or Gibaldi and Perrier [1982. Pharmacokinetics. Marcel Dekker, New York]. We discuss different approaches for the construction of appropriate optimality criteria, and find sharper upper bounds on the number of support points of locally optimal discrimination designs than those given by Caratheodory's Theorem. These results greatly facilitate the numerical construction of optimal designs. Various examples of optimal designs are then presented and compared to different other designs. Moreover, to protect the experiment against misspecifications of the nonlinear model parameters, we adapt the design criteria such that the resulting designs are robust with respect to such misspecifications and, again, provide several examples, which demonstrate the advantages of our approach. 相似文献
87.
弗·施勒格尔对浪漫主义有重要影响,反讽是他的重要概念之一。修辞学上的反讽与浪漫反讽是截然不同的,浪漫反讽具有重要的哲学方法论地位,它虽与形式逻辑相对,但却不是完全的非理性。对弗·施勒格尔来说,反讽是解决二元对立,达致统一哲学的唯一路径。 相似文献
88.
针对目前自动窗帘需要通过按钮或遥控器且只能实现近程控制的现状,提出了一种以STM32F103芯片为核心,
结合Wi-Fi通信技术和互联网技术,能够简单有效地对自动窗帘进行远程控制的解决方案。方案采用模块化的设计思
路,重点分析了系统无线通信模块、继电器模块、按键模块、电源保护和电平转换模块的设计过程,介绍了系统的基本工
作原理和操作方法,设计了基于TCP通信协议的服务端和客户端软件以通过互联网或者个人移动设备实现窗帘的远程
控制。实际结果表明,该方案可以应用于家居或办公环境,具有稳定性高、操作简单等特点。 相似文献
89.
In this paper, a mixture model under multiplicative censoring is considered. We investigate the estimation of a component of the mixture (a density) from the observations. A new adaptive estimator based on wavelets and a hard thresholding rule is constructed for this problem. Under mild assumptions on the model, we study its asymptotic properties by determining an upper bound of the mean integrated squared error over a wide range of Besov balls. We prove that the obtained upper bound is sharp. 相似文献
90.