查询词典 efficient estimator

Some troubles emerge when we use regression estimator in such a case:in a continuous survey research,when the prior sample and the present sample are independent and they have different elements,we can not compute the regression coefficient.

作连续调查研究抽样时经常用到回归估计。如果前后两个样本相互独立，并且它们所包含的元素不同，就无法直接计算出回归系数。

Asymptotic Normality of Wavelet Estimator in Heteroscedastic Regression Model Han-Ying Liang;Yi Lu

多媒体在高校教学中的应用王海霞；周军

In the second part , also under NA assumption, we worked on the consistency of kernel estimator of regression function in the nonparametric regression model Y_i =g+ε_i.

第二部分：我们研究了样本为NA相依的情况下，非参数回归模型Y_i=g+ε_ii=1，2，…，n中，回归函数核估计的强，弱相合性。

In chapter 1, regression models with censored data, LSE for censored regression models and LAD estimation for models with fixed censoring point are introduced. Then, we state our main results for LAD estimator of nonlinear regression models with randomly censored data, including consistency, boundedness in probability and asymptotic normality. The proofs of our main theorems are given in detail. In chapter 2, we state the main difficulty of obtaining numerical solution for censored LAD estimation, and recall the history of studies on this problem including some anterior algorithms.

在第一章，首先介绍删失线性回归模型的基本概念和性质，并对已有的估计方法，如最小二乘估计、固定点删失的最小一乘估计等做了简单的回顾；然后，把固定点删失线性回归模型的最小一乘估计方法推广到了随机删失、非线性模型的情形，并得到了估计量的一些渐近性质，如相合性、渐近正态性等；最后，给出主要结果的详细证明过程。

For getting the major characteristic edges without confusions by undesired structures like muscle edges, we integrate a star-like edge detection filter named "Asterisk Filter" with the Canny Edge Detection in the image preprocessing. In addition, we also propose a new contour tracking method named "One-Pixel Rolling Ball Contour Tracking" for getting the boundary information in a binary image which is a link-list data structure. Instead of using a regression curvature estimator, PCA is used for better curvature estimation from a discrete bony contour.

为了从影像上取得骨头特徵边缘，将不重要的肌肉视为杂讯滤除，我们引用一种星形滤波器－Asterisk Filter，搭配Canny边缘检测法，做为这类影像的前处理；另外，为了将骨头的边缘精确地追踪出来，我们提出滚球边界追踪法，来对二值化影像进行边缘追踪，藉此获得边缘的串列资料结构；我们采用以主成分分析(Principle Component Analysis，简称PCA)取代原本以回归方法来计算的曲率，以取得更佳的曲率估测值，其可提高计算之参数的准确性。

In this paper,two nonlinear anisotropic diffusion filtering methods are presented and they are based on the multispectral anisotropic diffusion models proposed by Pope and Acton.We build a couple of new diffusion coefficients in partial derivative equation based on Tukey's biweight estimator error norm by recurring to the relationship between robust statistics and anisotropic diffusion incorporated with the nonlinear time-dependent cooling technique for gradient threshold.

在Pope和Acton提出的两个多光谱图像各向异性扩散滤波模型的基础上，通过各向异性扩散和稳健统计学的联系，建立了基于B iwe ight Estim ator误差模型的扩散系数，同时利用非线性退化技术对梯度阈值的改进，提出了两个基于各向异性扩散方程的非线性滤波方法。

However,for the large dimensional data.the sample covariance matrix is not a good estimator of the population counterpart.Many methods of parametric estimations and tests for multivariate statistical problems can not be simply used to deal with large dimensional data.

但是由于经典的大样本理论都是假定维数很小是固定的，故而经典极限理论并不适宜解决大维随机数据问题，很多多元问题的模型参数估计、模型检验的统计量已有的结果对大维海量数据并不能平凡推广。

Consistency of an estimator is an important property, but it alone does not allow us to perform statistical inference.

估计量的一致性是一条重要性质，但我们并不能只靠它来进行统计推断。

Moreover, an Adaptive RM algorithm is proposed to adjust RM estimator by steepest descent method.

该运算复杂度远低于现有的盲信道估计搜索算法，并且适用于信道阶数较大、搜索算法不能处理的情况。

The signal components of interest in the interference frequency are also sunk while eliminating narrow band interference in direct sequence spread spectrum system by conventional NBI suppression techniques based on the estimator/subtracter in time domain, so the signal of interest is damnified inevitably.

传统的基于时域估计/相减的直接序列扩频系统窄带干扰抑制技术在对干扰陷波的同时，也将干扰频率处的信号分量陷去，不可避免地对有用信号产生损伤。

He became prime minister in 1997 and won international acclaim for his role in the Northern Ireland peace process.

他在1997年成为总理，并且因为在北爱尔兰的和平进程中发挥的作用受到国际社会的赞许。

Mixed Page Sorting Method Using the cuttable user model, this thesis proposes a mixed page sorting method by using cutted user model in server-side and complete user model in client-side.

隐私分级利用的混合式页面排序方法针对个性化搜索中搜索结果排序的问题，本文利用隐私可控开放的用户偏好模型，提出一个在客户端和服务器端分步进行的隐私分级利用的混合式页面排序方法。