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101.
三维平衡多水平轮换设计及其连续性估计方法研究   总被引:2,自引:0,他引:2       下载免费PDF全文
陈光慧  刘建平 《统计研究》2009,26(11):100-105
 针对现行多水平轮换调查存在的一系列问题,本文提出三维平衡多水平轮换模式设计及其广义组合估计方法。在这套设计方法中,将各种偏差和两类相关关系引入到广义组合估计量公式中,提高了估计量的准确性,同时在多目标调查下还应用最优化方法确定一套最优系数,使得连续性的多目标调查的整体估计精度达到最高,同时又兼顾各类目标量的精度要求。这套系统化、理论化的设计方法将为我国未来开展多水平轮换调查提供理论指导。  相似文献   
102.
Mixture experiments are often carried out in the presence of process variables, such as days of the week or different machines in a manufacturing process, or different ovens in bread and cake making. In such experiments it is particularly useful to be able to arrange the design in orthogonal blocks, so that the model in tue mixture vanauies may ue iitteu inucpenuentiy or tne UIOCK enects mtrouuceu to take account of the changes in the process variables. It is possible in some situations that some of the ingredients in the mixture, such as additives or flavourings, are present in soian quantities, pernaps as iuw a.s 5% ur even !%, resulting in the design space being restricted to only part of the mixture simplex. Hau and Box (1990) discussed the construction of experimental designs for situations where constraints are placed on the design variables. They considered projecting standard response surface designs, including factorial designs and central composite designs, into the restricted design space, and showed that the desirable property of block orthogonality is preserved by the projections considered. Here we present a number of examples of projection designs and illustrate their use when some of the ingredients are restricted to small values, such that the design space is restricted to a sub-region within the usual simplex in the mixture variables.  相似文献   
103.
In experimental design for response surface analysis, it is sometimes of interest to estimate the difference of responses at two points. If differences at points close together are involved, the design that reliably estimates the slope of the response surface is important. In particular, Hader and Park (1978 Hader , R. J. , Park , S. H. ( 1978 ). Slope-rotatable central composite designs . Technometrics 20 : 413417 .[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) suggested the concept of slope-rotatability and studied slope rotatable central composite designs. Until now, many response surface designs including central composite designs have been suggested for fitting second order response surface models. However, we often need to fit third-order polynomial regression models. In this article, we suggest extended central composite designs (ECCDs) to fit third-order models and find the necessary and sufficient conditions for slope-rotatability over all directions in the third-order polynomial models.  相似文献   
104.
The effect of one or more missing observations for response surface designs arranged in blocks are examined in this paper. The results as applied to a central composite design with orthogonal blocking, and an equirdial design with orthogonal blocking, are reported.  相似文献   
105.
The paper refers to a new procedure of Anderson and Hauck for the well-known problem of deciding whether two means of normal distributions with common but unknown variance differ within an admissible range. Analytical expressions for level and power of this method are derived and some numerical examples are given. A bound for the difference between real and no¬minal level is obtained which does not involve the variance.  相似文献   
106.
频带分析方法在我国景气周期波动中的应用   总被引:1,自引:0,他引:1  
摘  要:本文介绍了国外最近提出的基于频带分析的景气指标选择方法。本文首先利用带通滤波分离出我国实际GDP增长率的循环要素并把它作为基准指标,然后利用文中介绍的频带分析方法选择一致指标。在选择一致指标时发现,利用频带分析方法选择的固定资产投资指标,在时域上却未被入选。这表明选择指标时频带选择方法比时域选择方法选择范围更广。本文还分别基于频带方法和时域方法构造一致合成指数,这两者都能够较好地拟合GDP增长率的波动情况,但使用频带方法得到的结果略好一些  相似文献   
107.
Pressure is often placed on statistical analysts to improve the accuracy of their population estimates. In response to this pressure, analysts have long exploited the potential to combine surveys in various ways. This paper develops a framework for combining surveys when data items from one of the surveys is mass imputed. The estimates from the surveys are combined using a composite estimator (CE). The CE accounts for the variability due to the imputation model and the surveys’ sampling schemes. Diagnostics for the validity of the imputation model are also discussed. We describe an application of combining the Australian Labour Force Survey and the National Aboriginal and Torres Strait Islander Health Survey to estimate employment characteristics about the Indigenous population. The findings suggest that combining these surveys is beneficial.  相似文献   
108.
两相模型曾被用来分析SiCp颗粒增强的Al基复合材料在制备(冷却)过程中的热残余应力,但该模型无法计入颗粒之间的相互作用影响.本文在其过去提出的三相模型,并利用等效介质的物理特性,给出了计入颗粒浓度影响的MMCp界而残余应力的解析解的基础上,引入界口涂层以消除热残余应力,并对颗粒涂层的厚度与选材,利用细观力学原理进行优化设计,从而大大削弱直至完全可以消除界面处热残余应力的影响。  相似文献   
109.
复合材料的四相球模型及其应用   总被引:1,自引:0,他引:1  
本文提出复合材料的四相球模型来描述含涂层位于复合材料及合空心球复合材料的力学行为,得到了这两类复合材料有效模量预测的理论公式。通过与已有理论和实验结果的比较,证明了本文结果的合理性.  相似文献   
110.
综述了近几年钙钛矿锰氧化物磁电性质及CMR效应研究进展;综述了低场磁电阻研究现状,着重阐述了通过对钙钛矿锰氧化物的颗粒界面异质改性,实现低场磁电阻的方法,并提出利用A位稀土掺杂钙钛矿锰氧化物与金属颗粒复合实现低场磁电阻的设想。  相似文献   
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