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1.
In this paper we extend the definition of the influence function to functionals of more than one distribution, that is, for estimators depending on more than one sample, such as the pooled variance, the pooled covariance matrix, and the linear discriminant analysis coefficients. In this case the appropriate designation should be “partial influence functions,” following the analogy with derivatives and partial derivatives. Some useful results are derived, such as an asymptotic variance formula. These results are then applied to several estimators of the Mahalanobis distance between two populations and the linear discriminant function coefficients.  相似文献   

2.
This paper describes discrimination among multivariate autoregressive processes by the Bayes method. The asymptotic distribution of the discriminant function and estimation of the probability of misclassification are investigated.  相似文献   

3.
This article considers the use of adaptive ridge classification rules for classifying an observation as coming from one of two multivariate normal distributionsN(μ(1)Σ) andN(μ(2)Σ). In particular, the asymptotic expected error rates for a general class of these rules are obtained and are compared with that of the usual linear discriminant rule.  相似文献   

4.
Bayes判别在进行判别分析时考虑到各总体出现的先验概率、预报的先验概率及错判造成的损失,其判别效能优于其他判别方法.对Bayes判别方法详细介绍的基础上,利用R软件对一组舒张压和胆固醇数据分别进行Bayes判别分析、Fisher判别分析和基于距离的判别分析,对比三种不同方法下得到的判别结果,结果表明Bayes判别分析得到的分类结果精度较高,Bayes判别分析在医学领域有较好的应用前景.  相似文献   

5.
We consider the problem of discriminating between two independent multivariate normal populations, Np(μ1Σ1) and Np(μ2Σ2), having distinct mean vectors μ1 and μ2 and distinct covariance matrices Σ1 and Σ2. The parameters μ1, μ2, Σ1, and Σ2 are unknown and are estimated by means of independent random training samples from each population. We derive a stochastic representation for the exact distribution of the “plug-in” quadratic discriminant function for classifying a new observation between the two populations. The stochastic representation involves only the classical standard normal, chi-square, and F distributions and is easily implemented for simulation purposes. Using Monte Carlo simulation of the stochastic representation we provide applications to the estimation of misclassification probabilities for the well-known iris data studied by Fisher (Ann. Eugen.7 (1936), 179–188); a data set on corporate financial ratios provided by Johnson and Wichern (Applied Multivariate Statistical Analysis, 4th ed., Prentice–Hall, Englewood Cliffs, NJ, 1998); and a data set analyzed by Reaven and Miller (Diabetologia16 (1979), 17–24) in a classification of diabetic status.  相似文献   

6.
本文讨论了负相伴样本情形线性指数分布参数的经验Bayer(EB)双侧检验问题,利用概率密度函数的核估计构造了参数的经验Bayes检验函数,在适当的条件下证明了所提出的经验Bayes检验函数的渐近最优(a.o)性并获得了它的收敛速度,最后,给出一个有关本文主要结果的例子。  相似文献   

7.
Classification between two populations dealing with both continuous and binary variables is handled by splitting the problem into different locations. Given the location specified by the values of the binary variables, discrimination is performed using the continuous variables. The location probability model with homoscedastic across location conditional dispersion matrices is adopted for this problem. In this paper, we consider presence of continuous covariates with heterogeneous location conditional dispersion matrices. The continuous covariates have equal location specific mean in both populations. Conditional homoscedasticity fails when strong interaction between the continuous and binary variables is present. A plug-in covariance adjusted rule is constructed and its asymptotic distribution is derived. An asymptotic expansion for the overall error rate is given. The result is extended to include binary covariates.  相似文献   

8.
负相伴样本情形线性指数分布参数的经验Bayes检验问题   总被引:2,自引:0,他引:2  
讨论了负相伴样本情形线性指数分布参数的经验Bayes(EB)单侧检验问题.利用概率密度函数的核估计构造了参数的经验Bayes单侧检验函数,在适当的条件下证明了所提出的经验Bayes检验函数的渐近最优(a.o.)性并获得了其收敛速度.最后给出一个有关主要结果的例子.  相似文献   

9.
In this paper are considered the authors results that have been received in the last few years and are devoted to the research of functions mapping a finite linear space to itself. The characteristics of functions representing interest from the point of view of cryptography, geometrical properties of functions are resulted. This research is supported by RFFI (grants 99-01-00929 and 99-01-00941).Mathematics Subject Classifications (2000) 51E15, 51E20.  相似文献   

10.
The plug-in rule is used for the classification of random observations into one of two regular one-parametric distributions. The maximum likelihood estimates of unknown parameters obtained from the stratified training sample are used. The second-order asymptotic expansion in terms of the inverses of the training sample sizes is derived for the expected regret risk. The closed-form expressions of the expansion coefficients are applicable for the performance evaluation of the proposed classification rule. Klaipėda University, H. Manto 84, 5808 Klaipėda; Institute of Mathematics and Informatics, Akademijos 4, 2600 Vilnius, Lithuania. Published in Lietuvos Matematikos Rinkinys, Vol. 39, No. 2, pp. 220–230, April–June, 1999.  相似文献   

11.
The goal of classification (or pattern recognition) is to construct a classifier with small misclassification error. The notions of consistency and universal consistency are important to the construction of classification rules. A consistent rule guarantees us that taking more samples essentially suffices to roughly reconstruct the unknown distribution. Support vector machine (SVM) algorithm is one of the most important rules in two category classification. How to effectively extend the SVM for multicategory classification is still an on-going research issue. Different versions of multicategory support vector machines (MSVMs) have been proposed and used in practice. We study the one designed by Lee, Lin and Wahba with hinge loss functional. The consistency of MSVMs is established under a mild condition. As a corollary, the universal consistency holds true if the reproducing kernel Hilbert space is dense in C norm. In addition, an example is given to demonstrate the main results. Dedicated to Charlie Micchelli on the occasion of his 60th birthday Supported in part by NSF of China under Grants 10571010 and 10171007.  相似文献   

12.
Under some general assumptions on weight, we give a complete characterization of the Cauchy transform of continuous linear functionals on the weighted spaces of holomorphic functions in a ball. We construct an integral projection that sends the weighted spaces of measurable and n-harmonic functions in the ball onto the corresponding spaces of holomorphic functions.  相似文献   

13.
针对多观测样本分类问题,提出一种基于Kernel Discriminant CanonicalCorrelation(KDCC)来实现多观测样本分类的模型.该算法首先把原空间样本非线性的投影到高维特征空间,通过KPCA得到核子空间,然后在高维特征空间定义一个使类内核子空间的相关性最大,同时使类间核子空间的相关性最小的KDCC矩阵,通过迭代法训练出最优的KDCC矩阵,把每个核子空间投影到KDCC矩阵上得到转换核子空间,采用典型相关性作为转换核子空间之间的相似性度量,并采用最近邻准则作为多观测样本的分类决策,从而实现多观测样本的分类.在三个数据库上进行了一系列实验,实验结果表明提出的方法对于多观测样本分类具有可行性和有效性.  相似文献   

14.
用一种统一的方式,讨论了线性规划问题中常用的罚函数方法及其对偶性.并将这种方法应用到等式约束二次规划问题中.  相似文献   

15.
Summary In this paper we obtain asymptotic expansions for the distribution function and the density function of a linear combination of the MLE in a GMANOVA model, and for the density function of the MLE itself. We also obtain certain error bounds for the asymptotic expansions.  相似文献   

16.
在加权"线性损失"下讨论了负相伴样本情形连续型单参数指数族参数的经验Bayes(EB)检验问题.利用概率密度函数的核估计构造了参数的经验Bayes检验函数,并获得了它的渐近最优(a.o.)性,在适当的条件下证明了所提出的经验Bayes检验函数的收敛速度可任意接近O(n-1/2).  相似文献   

17.
线性指数分布参数的经验Bayes检验问题   总被引:2,自引:0,他引:2  
分别讨论了线性指数分布参数的经验Bayes(EB)单侧和双侧检验问题.利用概率密度函数的核估计分别构造了参数的经验Bayes检验函数,在适当的条件下证明了所提出的经验Bayes检验函数的渐近最优(a.o.)性并获得了它的收敛速度.最后,给出一个有关主要结果的例子.  相似文献   

18.
聚集数据线性模型参数的广义岭估计的相对效率   总被引:1,自引:0,他引:1  
对于聚集数据的线性模型,给出了参数的广义岭估计的两种相对效率,并得到了两种相对效率的上界.  相似文献   

19.
在详细分析线性流量阀工作原理的基础上,应用平面解析几何、微积分等相关概念,给出了不存在呈严格线性的流量阀的数学论证.在设计近似线性流量阀时,首先构造了"线性误差函数"用以刻画"过流面积"与角度之间的线性误差.之后在分析内孔为对称直线、对称1/2次曲线的基础上,设计出内孔为倒"S"形内孔曲线图,通过最小化线性误差函数,得到内孔曲线的最佳参数.最后针对外孔有磨损时,给出了设计方案.  相似文献   

20.
邢永丽  王迪 《大学数学》2021,37(1):108-111
当线性方程组中含有未知参数时,线性方程组解的情况往往需要进行讨论.本文给出了在非齐次线性方程组系数矩阵中含有未知参数且系数行列式等于零的情况下,判定对应参数值下方程组的解是无解还是有无穷多解的两个判定定理.和以前的方法比较,本文提出的讨论方法更直接.  相似文献   

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