Since 1952 the markowitz ’ s mean - variance portfolio theory inception , sur - rounding this issue which how to measure risks , it has generated a lot of risk mea - surement methods and bring a lot of portfolio models , such as mean - semivariancemethods , mean - downside risk methods , mean - absolute deviation methods , mean - absolute semideviation methods , mean - absolute downside risk , and soon . 1999 , duarte proposed a portfolio optimization uniform model that unifiedthe six methodologies mentioned above 自从1952年markowitz的均值-方差投资组合理论问世以来,围绕着如何对风险进行度量这一问题先后产生了许多的风险度量方法,带来了很多的投资组合模型,如均值-半方差法、均值-下滑风险方法、均值-绝对离差方法、均值-绝对半离差方法、均值-绝对下滑风险方法等等。
In this paper , based on the project benefit and risk hobby of personal consideration , the uncertainty concept of entropy is used to measure multiple angle and directional risk combining with the analysis method of traditional variance and probability , the connection of benefit and risk has been proposed , which will become a complete process of risk appraisal for increasing dependable of risk measurement 基于对投资项目收益及个人风险喜恶的考虑，本文根据熵度量不确定特征，结合传统方差法、概率分析等优点，综合考虑收益与风险之间的联系，多角度、多方位对风险进行度量，从而形成了一个完整的风险评价过程，以增加风险度量的可靠性。
This index then is decided to contain the fluctuation of both income and consumption instead of focusing only on one factor , and it should be measured by the squared resid of the time serial simulation of variables , rather than commonly used group variations or other indirect indices , which are quite different from formal researches . besides , the accuracy of the ecm model will be greatly underlined 在计量方法上,笔者分析了各种方法的利弊,最终放弃了前人常用的组间方差法、间接变量法和主观报告法,而使用了更切合经济含义且更具相关性、更客观的残差平方(对变量进行时间序列模拟后得到,稍后会作取对处理) 。
The analysis focuses on two aspects : firstly , the factors , such as economic developing level , structure of agro - economy , duality economy structure , educational and geological as well as resources distribution based on traditional economical theory are analyzed and discussed , and for the first time the inequality between the laborage level and the chance of obtaining employment is decomposed in quantity , it makes clear that the inequality of the chance of obtaining employment is more important than the laborage level in different rural areas ; and on the basis of some quantity model on the data from different provinces and cities , the reasons caused internal difference are be contrastively analyzed and the micro - factors which effect the increasing speed of farmers income inequality are discovered 分析主要从两方面进行：首先依据传统区域经济发展理论，从各地经济发展水平、农村产业结构、二元经济结构、文化素质及地理位置等方面进行了论述与实证，并首次利用对数方差法对区域间收入差异中的乡镇工业“工资”与“就业机会”不平等进行了数量分解，结果表明， “就业机会”不平等是引起地区非农收入差异更重要的原因；同时，针对各收入区组建立了数量模型，对其内部差异产生的因素进行浙江大学博士学位论文中国经济转型期地区农民收入差异研究.二.
Then the research of image enhancement based on of plateau equalization algorithm and genetic algorithm is done then in this chapter . image segmentation with algorithm of 2d - maximal variance between - class and region growing is accepted to eliminate the background and the isolated noise points which can not be the target 论文在红外目标检测方面,以对经过预处理的图像进行分割为切入点,采用二维类间方差法和局域生长法来进行图像的分割,消除了原始图像中一些不可能为目标的孤立噪声点和大面积的背景区域。
In the first part , we analyze the risk and reasons that a securities corporation in china is facing at present , then develops a securities corporation risk control system based on the realities in china by the ways of advanced qualitative management pattern from oversea . in the second part , we consider the existing situations that market risks became a major problem to a securities corporation , we have a method to measure developed market risk by adopting an advanced quantitative model var which is popular internationally , and we focus on studing risk metrics ( var - covar ) application in securities market of china practically . we conclude that var model is useful and effective at controlling market risks in china by our analysis and test 第一部分通过对证券公司风险及风险成因的分析，借鉴国外先进管理模式提出了构建符合中国国情的证券公司风险控制体系，对目前我国证券公司主要业务的风险点及风险管理进行阐述，并佐以案例；第二部分针对市场风险日益成为证券公司主要风险的现状，引入了国际上最广泛使用的市场风险控制方法? ?风险价值法( var ) ，从实用角度重点研究了方差协方差法在我国证券市场的应用，通过实证分析得出了在我国使用var控制市场风险是切实可行的结论。
