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41.
考虑图像投影鉴别分析问题,为提高特征抽取的速度和识别率,利用图像矩阵直接构造图像散布矩阵,在具有统计不相关的条件下将Foley-Sammon鉴别分析(FSLDA)转化为两目标约束优化问题,并给出了有效投影向量的概念;根据多目标优化的最优性条件可将求取有效投影向量的问题归结为求广义特征方程的最大特征值对应的特征向量,并据此进行特征抽取,进而提出了两目标最优图像投影鉴别分析方法。与其他鉴别投影分析方法相比,该方法具有以下特点:(1)可直接由图像矩阵构建散布矩阵;(2)有效投影向量具有统计不相关性;(3)训练样本的类内散布矩阵不必为可逆的,也不需要求某种形式矩阵的逆。在ORL标准人脸库和NUST603人脸库上的试验结果表明,上述图像投影鉴别分析方法在识别性能上较以往的方法有一定的提高,尤其是特征抽取的速度有明显的提高。 相似文献
42.
When the necessary conditions for a BIBD are satisfied, but no BIBD exists, there is no simple answer for the optimal design problem. This paper identifies the E-optimal information matrices for any such irregular BIBD setting when the number of treatments is no larger than 100. A- and D-optimal designs are typically not E-optimal. An E-optimal design for 15 treatments in 21 blocks of size 5 is found. 相似文献
43.
Constantine Gregory Magda 《统计学通讯:理论与方法》2013,42(18):1901-1918
The concept of a circular design is defined and when proper balance for various effects is assumed, its universal optimality is proved over the class of all designs with the same set of parameters, Such designs are shown to minimize the variance of the best linear unbiased estimators of contrasts of residual and direct effects over the class of equireplicated designs. All models assume first order residual effects and are of a circular nature. The proofs are presented in a unified manner for several models at a time. They are based on certain matrix domination which occurs when parameters are eliminated from a linear modelj this latter fact is proved for a general linear model. 相似文献
44.
制度经济学的外部性理论可以证明:只有将京津冀地区独立研发的外部性转为内部性才能使三地研发资源的配置达到最优。帕累托最优理论也证明:通过资源的整合可以达到在没有使京津冀三方中任何一方变坏的前提下,使一方变好,最终达到最优。以这两个理论为基础,通过构建包含有信息协调与共享,市场交易与合约管理,京津冀研发联盟政府支持,关系与政策协调等功能的京津冀区域研发联盟就能够实现京津冀在科技资源配置上达到共赢的目标。 相似文献
45.
Carl M.-S. Lee 《统计学通讯:理论与方法》2013,42(3):765-783
An attempt of combining several optimality criteria simulaneously by using the techniques of nonliear programming is demonstrated. Four constrained D- and G-optimality criteria are introduced, namely, D-restrcted, Ds-restricted, A-restricted and E-restricted D- and G-optimality. The emphasis is particularly on the polynomial regression. Examples for quadratic polynomial regression are investigated to illustrate the applicability of these constrained optimality criteria. 相似文献
46.
A sequence of empirical Bayes estimators is defined for estimating, in a two-sample problem, the probability that X ≥ Y. The sequence is shown to be asymptotically optimal relative to a Ferguson Dirichlet process prior. 相似文献
47.
Here, the optimality of block design with interference effect from neighboring unit under a general non additive model is investigated, which allows for the presence of interactions among the treatments applied in the adjacent plots. A non additive model with interference × direct effects of treatments is considered as these effects contribute significantly to the response. A class of complete block designs balanced for interference effects from left neighboring unit is shown to be universally optimal for the estimation of direct and interference effects of treatments and two such series of designs have been constructed. Furthermore, considering direct treatment × block non additivity with interference effects, the optimality is studied and the optimal designs are obtained. 相似文献
48.
Joachim Kunert 《统计学通讯:理论与方法》2013,42(21):2665-2671
Magda (1980) introduced a model for repeated measurements designs with a circular structure of the residual effects. He proved the universal optimality of circular balanced uniform designs over a subclass of the possible designs. We strengthen his result to optimality over the set of all designs with the same number of experimental units, periods and treatments. 相似文献
49.
Mausumi Bose 《Australian & New Zealand Journal of Statistics》1998,40(2):241-248
In the usual repeated measurements designs (RMDs), the subjects are all observed for the same number of periods and the optimum RMDs require specified numbers of subjects, usually depending on the number of treatments to be used. In practice, it is sometimes not feasible to meet these requirements. To overcome this problem, alternative designs are suggested where any number of available subjects may be used and they may be observed for different periods. These designs are based on suitable serially balanced sequences which are shown to be optimal. Moreover, besides the usual direct and residual effects, the model considered has an extra term due to the interaction effect between them. The recommended designs are universally optimal in a very general class. 相似文献
50.
求二次型最大、最小值方法初探 总被引:1,自引:0,他引:1
吴丽萍 《吉林工程技术师范学院学报》2008,24(11):95-96
关于求二次型Q(x)=x^TAx的最大、最小值,在许多实际问题中都有广泛的应用。这类问题可化为x是在一组单位向量中的变量的优化问题。本文介绍了几种求二次型在一定限制条件下的最大、最小值的方法。 相似文献