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21.
本文给出了一种化具有多个分段点,且在各区间段上的表达式为多项式函数的分段函数为初等函数的具体方法.  相似文献   
22.
Technology continues to challenge the public relations practitioner to find ways to inform key constituents. The new technology has given rise to the “new journalism” that includes a declining traditional media and exploding internet media filled with websites and bloggers. The question posed by this research asks: Does the public relations practitioner inherit the same protection offered by “qualified privilege” that is most often associated with the traditional “press” or “reporter?” The research lays a foundation with an examination of defamation and the defense of qualified privilege. The research concludes that if information gathered by the public relations practitioner meets the “intent” and “content” tests, the information qualifies as news. Passing the “news” test, the defense of “qualified privilege” also attaches to the public relations practitioner.  相似文献   
23.
Low dose risk estimation via simultaneous statistical inferences   总被引:2,自引:0,他引:2  
Summary.  The paper develops and studies simultaneous confidence bounds that are useful for making low dose inferences in quantitative risk analysis. Application is intended for risk assessment studies where human, animal or ecological data are used to set safe low dose levels of a toxic agent, but where study information is limited to high dose levels of the agent. Methods are derived for estimating simultaneous, one-sided, upper confidence limits on risk for end points measured on a continuous scale. From the simultaneous confidence bounds, lower confidence limits on the dose that is associated with a particular risk (often referred to as a bench-mark dose ) are calculated. An important feature of the simultaneous construction is that any inferences that are based on inverting the simultaneous confidence bounds apply automatically to inverse bounds on the bench-mark dose.  相似文献   
24.
Generalized additive models for location, scale and shape   总被引:10,自引:0,他引:10  
Summary.  A general class of statistical models for a univariate response variable is presented which we call the generalized additive model for location, scale and shape (GAMLSS). The model assumes independent observations of the response variable y given the parameters, the explanatory variables and the values of the random effects. The distribution for the response variable in the GAMLSS can be selected from a very general family of distributions including highly skew or kurtotic continuous and discrete distributions. The systematic part of the model is expanded to allow modelling not only of the mean (or location) but also of the other parameters of the distribution of y , as parametric and/or additive nonparametric (smooth) functions of explanatory variables and/or random-effects terms. Maximum (penalized) likelihood estimation is used to fit the (non)parametric models. A Newton–Raphson or Fisher scoring algorithm is used to maximize the (penalized) likelihood. The additive terms in the model are fitted by using a backfitting algorithm. Censored data are easily incorporated into the framework. Five data sets from different fields of application are analysed to emphasize the generality of the GAMLSS class of models.  相似文献   
25.
Longitudinal data often contain missing observations, and it is in general difficult to justify particular missing data mechanisms, whether random or not, that may be hard to distinguish. The authors describe a likelihood‐based approach to estimating both the mean response and association parameters for longitudinal binary data with drop‐outs. They specify marginal and dependence structures as regression models which link the responses to the covariates. They illustrate their approach using a data set from the Waterloo Smoking Prevention Project They also report the results of simulation studies carried out to assess the performance of their technique under various circumstances.  相似文献   
26.
民族院校应该是以全面服务于非主流族群作为自身的基本定位,民族院校的新闻传播学科要在准确理解这一定位的基础上确立自身的发展路径,以鲜明的特色建构来强化自身的学科核心竞争力。  相似文献   
27.
教师的专业化教育是教师教育现代化的重要特征。教育专业的高等数学课程如何在“教师专业化”框架中获得发展,是优化教育专业课程体系的关键所在。高等数学课程编制应当坚持以知识性、探究性和延展性为特点的价值取向。  相似文献   
28.
建国以来,中国的发展以1978年为界分为前后两个30年。前30年,中国在计划经济体制下,顺利完成了国民经济的恢复任务、社会主义改造,并建立起比较完善的国民经济体系。后30年,中国通过改革开放,走上了一条中国特色社会主义发展道路,初步实现了国家的繁荣强盛,但是也面临着发展的困境。如果说,正是通过30年的改革开放,使中国真正跻身世界大国行列,那么中国在今后的发展中解决一系列发展难题,也必然要靠继续深化改革扩大开放。因此,认真总结中国改革开放的经验教训,为实现中华民族的伟大复兴就是我们必须要做的重要工作。  相似文献   
29.
Summary. Using a novel method, the paper investigates the influence of social group identities on attitudes and on voting in a variety of political contexts. Examining the major regions of Britain, Canada and the USA, we find considerable national and regional diversity in the nature of social cleavages. For example, social class and race had widely different effects across societies, but within societies their effects on attitudes and on voting were very similar. However, despite that, age and religion had a similar effect on attitudes across societies; the effects on voting varied considerably. The significant within-country differences underline the importance of using region, rather than country, as the unit of analysis. More importantly, these results highlight the role of political context, especially competing cleavages and the structure of party competition, in the establishment of politically relevant social cleavages.  相似文献   
30.
周建人在五四后期在恋爱、婚姻、离婚问题上更多地注重个体的自由、价值和觉醒。他认为,真诚的恋爱本是人生的花,是精神的高尚产品;理想的配偶选择应以个人本身性质上的各种美德为标准:以爱情的有无为婚姻离合的原则。婚恋的个人自由和独立有利于种族的完善、国家的进步,也是妇女解放和冲破家族制度的重要手段。因此,其婚恋观的一个重要诉求是男女平等,呈现出对妇女解放各个问题理性而具体的思考。  相似文献   
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