Unbiased statistical estimation functions for parameters in presence of nuisance parameters

We consider the problem of estimating a vector interesting parameter in the presence of nuisance parameters through vector unbiased statistical estimation functions (USEFs). An extension of the Cramer—Rao inequality relevant to the present problem is obtained. Three possible optimality criteria in the class of regular vector USEFs are those based on (i) the non-negative definiteness of the difference of dispersion matrices (ii) the trace of the dispersion matrix and (iii) the determinant of the dispersion matrix. We refer to these three criteria as M-optimality, T- optimality and D-optimality respectively. The equivalence of these three optimality criteria is established. By restricting the class of regular USEFs considered by Ferreira (1982), we study some interesting properties of the standardized USEFs and establish essential uniqueness of standardized M-optimal USEF in this restricted class. Finally some illustrative examples are included.     

DT-optimum designs for model discrimination and parameter estimation

The paper introduces DT-optimum designs that provide a specified balance between model discrimination and parameter estimation. An equivalence theorem is presented for the case of two models and extended to an arbitrary number of models and of combinations of parameters. A numerical example shows the properties of the procedure. The relationship with other design procedures for parameter estimation and model discrimination is discussed.     

Cost-cautious designs for confirmatory bioassay

Confirmatory bioassay experiments take place in late stages of the drug discovery process when a small number of compounds have to be compared with respect to their properties. As the cost of the observations may differ considerably, the design problem is well specified by the cost of compound used rather than by the number of observations. We show that cost-efficient designs can be constructed using useful properties of the minimum support designs. These designs are particularly suited for studies where the parameters of the model to be estimated are known with high accuracy prior to the experiment, although they prove to be robust against typical inaccuracies of these values. When the parameters of the model can only be specified with ranges of values or by a probability distribution, we use a Bayesian criterion of optimality to construct the required designs. Typically, the number of their support points depends on the prior knowledge for the model parameters. In all cases we recommend identifying a set of designs with good statistical properties but different potential costs to choose from.     

模糊等价关系下的收敛

研究了模糊等价关系,证明了一个模糊等价关系生成一个拓扑族,并定义了关于该拓扑族的收敛性;最后证明了两个cauchy序列的模糊关系值收敛于闭区间[0,1]中的某个点.     

Construction of optimal designs in random coefficient regression models

We consider the problem of optimal experimental design in random coefficient regression models with respect to a quadratic loss function. By application of WHITTLE'S general equivalence theorem we obtain the structure of optimal designs. An alogrithm is given which allows, under certain assumptions, the construction of the information matrix of an optimal design. Moreover, we give conditions on the equivalence of optimal designs with respect to optimality criteria which are analogous to usual A-D- and _E/-optimality.     

Optimum Designs for Parameter Estimation in Linear Mixture Models with Synergistic Effects

In this article, we derive optimum designs for parameter estimation in a mixture experiment when the response function is linear in the mixing components with some synergistic effects. The D- and A-optimality criteria have been used for the purpose. The Equivalence Theorem has been used to check for the optimality of the proposed designs.     

奈达理论新解“等效翻译”非奈达理论——“等效翻译”乃中西方译论家误读而产生的翻译标准

受西方误读和误译的影响,中国译论家将奈达的Functional Equivalence误译成"功能对等";后来"功能对等"进一步被错误地推演为"等效翻译"。"等效翻译"原则是中国一些翻译理论家在西方译论家误读误译Equivalence的基础上自己创造的翻译原则;它的理论基础违背了翻译的本质,没有实质理论内容和体系。Functional Equivalence被译成"功能对等"曲解了奈达翻译理论,"功能对等"被推演为"等效翻译"进一步曲解了奈达翻译理论。     

符号学语言观指导下语码转换的翻译研究

语码转换这种常见的语言表达形式在文学文本中往往是作者有意所为,具有特定的诗学效果。但语码转换的翻译,由于多种语码并存,常常给译者造成困难。从符号学语言观的三种意义出发分析文学文本中的语码转换,并以具体的译例讨论了各种翻译手段的利与弊,从而提出译者应正视语码转换的可译性限度问题,尽最大努力再现原作,以在最大程度上实现奈达提出的“译语的信息接受者对译文的反应与源语接受者对原文的反应程度基本相同”的对等标准。