查询词典 sample covariance

This thesis has mainly contributed two results in theory: one is that the covariance matrix is not positive definitive if the number of sampling is least than the number of variables, the other is that the covariance matrix of discrete sample is positive definitive if and only if the sum of every random column vector of data matrix is non I-linear combination.

本论文在理论上，主要得出两个新的结果：ⅰ抽样调查中，若样本的个数少于变量的个数则样本协方差矩阵恒为非正定；ⅱ离散型样本协方差矩阵正定的充要条件是样本资料阵的各随机列向量是非I-线性组合。

First we construct a covariance matrix from sample images, then compute the eigenvalues and corresponding eigenvectors of the covariance matrix, construct a feature matrix with the eigenvectors. Then every images in database can be projected into the feature matrix and gain a projection vector, so does the input image. Then we can judge the resemblance between input image with each image in database by computing the distance between their projection vectors.

我们首先根据采集的样本图像构造一个协方差矩阵，然后求取该矩阵的特征值，以这些矩阵特征值对应的特征向量构造出一个特征空间，然后将输入图像向该特征空间映射，将获取的映射系数与样本库中图像的映射系数进行距离计算，根据计算出的距离判定输入图像与样本图像间的匹配程度。

Owing to the possible measurement error of variance and covariance for Markowitz's M-V model, in the present study, it employs two static models and two dynamic models, which are the sample covariance model, implicit factor mode!, implicit factor GARCH model and full-factor multivariate GARCH model.

基於Markowitz(1952)提出的M-V投资组合模型可能造成变异数及共变异数衡量的偏误，因此，本文以样本共变异数模型、内含因素模型等两我种静态模型，并参酌Alexander and Leigh(1997)的内含因子GARCH模型与Vrontos et al。

Events,Operation and Relation of Sets, Classical Probability, Geometrical Probability , Statistical Stability of a Frequency, Axioms of Probability, Conditional Probability, Total Probability Theorem, Bayes' Rule,Independent Events,Independent Repeated Trials, One Dimensional Random Variables, Discrete Random Variables, Distribution Function of a Random Variables , Continuous Random Variables, Normal Distribution, Distribution of a Function of a Random Variable, Multidimensional Random Variables, Joint Distribution Function, Marginal Distribution Function,Discrete Two—Dimensional Random Variables,Continuous Two—Dimensional Random Variables, Independent Random Variables, Distribution of Functions of Random Variables,Expectation,Variance, Covariance, Coefficient of Correlation, Bivariate Normal Distribution, Law of Large Numbers, The Central Limit Theorems, Sample and Population ,Chi—Squared, T and F Distributions , Sampling Distributions , Point Estimation , Interval Estimation , Testing Hypotheses , A Test of Significance for Parameters in a Single Sample From a Normally Distributed Population , A Test of Significance for Parameters in Two Sample From Normally Distributed Populations .

本课程的主要内容：概率的概念与运算、随机变量及其分布、随机变量的数字特征与极限定理、数理统计的基本概念、估计和检验的基本方法，随机事件与概率随机事件、事件的关系与运算、几何概率、统计概率等，条件概率、全概率公式、贝叶斯公式、事件的独立性、二项概率公式，随机变量的概念、离散型随机变量、随机变量的分布函数、连续型随机变量、随机变量函数的分布，多维随机变量及其分布函数、边缘分布函数、随机变量的独立性、二维随机变量函数的分布，数学期望、方差、协方差和相关系数、大数定律、中心极限定理，总体与样本， X 2-分布、 t-分布和 F-分布，统计量及抽样分布，假设检验的基本概念、单个正态总体参数的显著性检验、两个正态总体参数的显著性检验。

In a special case of 2 dimensional variables, the probability of the positive definitiveness of the discrete sample covariance matrix is given in term of sample size and variable dimension. Based on the results, the optimal sample size is provided in this thesis.

推出了离散型样本协方差矩阵正定的充要条件，得到了求离散型样本协方差矩阵正定概率的模型，建立了特殊情况下的抽样优化模型。

The sample proportion has mean and variance and (3.7) In Section 14.1.4 we show that for , and have covariance (3.8) The sample proportions have a large-sample multivariate normal distribution.

样品比例有手段和变化并且(3.7)在部分14.1.4 我们显示那为，和有协变性(3.8)样品比例有大样品多维分布的正常分配。

Nevertheless, in many practical applications such as in low sample support or when the signal statistics are rapidly time-varying, we may not have enough sample to form the sample covariance matrix.

然而，常规的子空间估计方法由于涉及到阵列协方差矩阵的估计及其特征值分解，从而需要较高的计算复杂度。

The results show that the crystal form of the apophyllite sample from Huangshi of Hubei Province is mainly in tabular, and that of the sample from Punna of India is in columnar. The main elements of the both samples are Si, Ca and K, but Al and Na could be found in the sample from Huangshi of Hubei Province. The gas-liquid inclusion is mainly in apophyllite sample from Huangshi of Hubei Province, and the quartz and zeolite inclusions are mainly in the sample from Punna of India.

结果显示，湖北黄石鱼眼石样品的结晶形态以板状为主，印度浦那鱼眼石样品则以柱状为主；所有样品的主要元素均为Si，Ca和K，但湖北黄石鱼眼石样品中还含有Al和Na元素；湖北黄石鱼眼石样品以气液两相包裹体为主，印度浦那鱼眼石样品则以石英、沸石等晶体包裹体为主。

A sequenced method in consideration of the sample range was proposed to rationally array classifiers of a support vector machine with binary tree architecture. A sample distribution radius and a sample distribution distance were introduced to estimate sample range of all classes in high-dimension characteristic space. The classes with bigger sample range were classified earlier in the higher nodal point of the binary tree architecture, and were given wider classificatory areas in the characteristic space.

考虑到样本的分布情况对分类器推广能力具有较大影响，提出一种次序二叉树支持向量机多类算法，采用样本分布半径和样本分布距离估算各个类别的样本在高维特征空间中的分布情况，把分布半径较大的类别或者分布距离较大的类别较早地分出来，并且在特征空间中给其划分较大的分类区域。

We canconsider 29# sample isATP synthase beta chain; The peptides molecularweight of 53# sample are same with that of 43#, 45#, 52# sample and these samples shouldbe same protein, the Mowse score is 78 between 53# sample and Spliceisoform Short, greater than 66 is significant, We can consider 53# sample is Splice isoform Short.

其中，53#样品与Splice isoform Short的匹配分数是78，达到了显著，可以认为53#样品是Splice isoform Short，但根据该蛋白的功能特点，Splice isoform Short对耐盐方面的作用不是太大。

"Yes, now you can give yourself airs," she said, you have got what you wanted.

"对了，您现在高兴了，"她说道，这是您所期待的。

Then the LORD said to me: Rebel Israel is inwardly more just than traitorous Judah.

上主于是对我说：＂失节的以色列比失信的犹大，更显得正义。