Simple detection of outlying short time series

Sets of relatively short time series arise in many situations. One aspect of their analysis may be the detection of outlying series. We examine the performance of standard normal outlier tests applied to the means, or to simple functions of the means, of AR(1) series, not necessarily of equal lengths. Although unequal lengths of series implies that the means have unequal variances, that are only known approximately, it is shown that nominal significance levels hold good under most circumstances. Thus a standard outlier test can usefully be applied, avoiding the complication of estimating the time series' parameters. The test's power is affected by unequal lengths, being higher when the slippage occurs in one of the longer series     

电子商务立法的国际比较及对我国的启示

电子商务的迅速发展实质性地改变了传统市场交易的形式。而作为法律调整和规范的主要对象之一，交易形式的变化要求有新的法律规定与之相适应。在国际上，关于电子商务的立法活动已经形成了一种浪潮。而我国的电子商务立法工作却一直进展缓慢。其中有认识上的问题，更主要的是立法经验的不足。借鉴有关国家电子商务立法的先进经验，我国应当尽快建立和完善电子商务法制，这其中包括应当建立关于电子签名、电子商务认证、电子合同、电子支付等方面的法律规则与制度。     

Divergence-based estimation and testing with misclassified data

The well-known chi-squared goodness-of-fit test for a multinomial distribution is generally biased when the observations are subject to misclassification. In Pardo and Zografos (2000) the problem was considered using a double sampling scheme and ø-divergence test statistics. A new problem appears if the null hypothesis is not simple because it is necessary to give estimators for the unknown parameters. In this paper the minimum ø-divergence estimators are considered and some of their properties are established. The proposed ø-divergence test statistics are obtained by calculating ø-divergences between probability density functions and by replacing parameters by their minimum ø-divergence estimators in the derived expressions. Asymptotic distributions of the new test statistics are also obtained. The testing procedure is illustrated with an example.     

从环境和建筑看生态建筑设计

建筑师和生态学家对环境和建筑的认识存在着一定的差异。生态建筑设计需要建筑师借鉴生态学家的认识 ,建立一种整体的建筑观念。依托整体生态观和系统观念建立起来的整体生态建筑观包括两个方面的内容 :其一是建筑系统在全寿命过程中 ,持续地与周围生态系统环境相互作用 ;其二是建筑系统对周围生态系统会产生空间置换影响 ,而这种影响具有一定的空间范围     

大学英语学期测试种种

大学英语测试是大学英语教学中必不可少的一部分 ,合理的测试方法有助于推动教学质量的提高。通过对现行学期测试题型与内容优缺点的阐释 ,提出了改进学期测试的想法 ,并对学期测试中听力、阅读、词汇与结构、作文及口语的题型与内容以及评卷工作的改进进行了具体的探讨。     

An affine‐invariant multivariate sign test for cluster correlated data

The author presents a multivariate location model for cluster correlated observations. He proposes an affine‐invariant multivariate sign statistic for testing the value of the location parameter. His statistic is an adaptation of that proposed by Randles (2000). The author shows, under very mild conditions, that his test statistic is asymptotically distributed as a chi‐squared random variable under the null hypothesis. In particular, the test can be used for skewed populations. In the context of a general multivariate normal model, the author obtains values of his test's Pitman asymptotic efficiency relative to another test based on the overall average. He shows that there is an improvement in the relative performance of the new test as soon as intra‐cluster correlation is present Even in the univariate case, the new test can be very competitive for Gaussian data. Furthermore, the statistic is easy to compute, even for large dimensional data. The author shows through simulations that his test performs well compared to the average‐based test. He illustrates its use with real data.     

学校早期读写训练对儿童读写成绩的影响

利用儿童家庭一学校早期语言与识字能力系列测验对每个目标儿童语言与识字能力发展进行了评定，并解释了这些测量结果与儿童学校早期语言与识字测量指标之间的关系。结果表明：(1)儿童丰富的同伴关系与词汇量、应变识字能力、下定义能力和理解力有关；(2)教师语言的丰富性有助于儿童语言与识字能力发展；(3)识字课程变量与三岁儿童的应变识字成绩和四岁儿童词汇量和故事理解有关；(4)影响儿童语言与识字能力的因素不是单一的，而是一个因素群。     

略论邓小平理论萌芽的界定及其标志

作为邓小平理论萌芽的标志不是某一具体的时间、论著、观点。对邓小平理论萌芽应作出系统的、全面的科学界定。邓小平理论萌芽的标志应该是时间段、论著链、观点网     

外语考试的计算机语料库建设

计算机语料库是以语篇为基础对语言进行研究的一门新兴交叉型学科。20世纪90年代以来,应用不断更新的计算机技术建立的各类语料库,使语言研究的手段与方法都发生了巨大变化。但在开发以各类考试材料为语料的专门用途语料库方面,发展却相对滞后。大学英语四、六级考试是我国高等教育最重要的大规模外语考试,对推动大学外语教学起到了功不可没的作用。研究并建成大学英语四、六级考试计算机语料库,对大学外语教学具有很大意义。