中国农村金融发展与农村居民收入增长关系的经验研究

基于1978-2007年的相关数据,运用Johansen协整检验、格兰杰因果关系检验、脉冲响应函数和方差分解等方法对中国农村金融发展与农村居民收入增长关系进行检验。研究认为：农村金融发展与农村居民收入增长存在长期协整关系,并且只是存在单向因果关系。     

Precedence tests and Lehmann alternatives

G = F ^k (k > 1); G = 1 − (1−F) ^k (k < 1); G = F ^k (k < 1); and G = 1 − (1−F) ^k (k > 1), where F and G are two continuous cumulative distribution functions. If an optimal precedence test (one with the maximal power) is determined for one of these four classes, the optimal tests for the other classes of alternatives can be derived. Application of this is given using the results of Lin and Sukhatme (1992) who derived the best precedence test for testing the null hypothesis that the lifetimes of two types of items on test have the same distibution. The test has maximum power for fixed κ in the class of alternatives G = 1 − (1−F) ^k , with k < 1. Best precedence tests for the other three classes of Lehmann-type alternatives are derived using their results. Finally, a comparison of precedence tests with Wilcoxon's two-sample test is presented. Received: February 22, 1999; revised version: June 7, 2000     

Symbolic computation for approximating distributions of some families of one and two-sample nonparametric test statistics

A conditional saddlepoint approximation was provided by Gatto and Jammalamadaka (1999) for computing the distribution function of many test statistics based on dependent quantities like multinomial frequencies, spacing frequencies, etc. The considerable complexity of the formulas involved can be bypassed by symbolic computation. This article illustrates the effectiveness of symbolic computation to evaluate the saddlepoint approximation for the likelihood ratio, the exponential score, and the Wald-Wolfowitz test statistics. The case of composite hypotheses is also discussed.     

指数族分布中参数的经验贝叶斯估计

指数族分布是一类应用广泛的分布类,包括了泊松分布、Gamma分布、Beta分布、二项分布等常见分布.在非寿险中,索赔额或索赔次数过程常常被假定服从指数族分布,由于风险的非齐次性,指数族分布中的参数θ也为随机变量,假定服从指数族共轭先验分布.此时风险参数的估计落入了Bayes框架,风险参数θ的Bayes估计被表达“信度”形式.然而,在实际运用中,由于先验分布与样本分布中仍然含有结构参数,根据样本的边际分布的似然函数估计结构参数,从而获得风险参数的经验Bayes估计,最后证明了该经验Bayes估计是渐近最优的.     

论全国公共英语等级考试设计特色

比较传统语言测试与交际语言测试,列举各自的优势与不足,分析PETS的设计特色,说明PETS是以交际性测试理论为基础,并借鉴传统语言测试的手法而建立的、全面考查语言运用能力的较为先进的考试体系.     

论标准分数在确立学生多科考试总成绩相对位次中的应用

标准分数是将原始卷面分数经过某种数学公式转换后,扣除难度和区分度等客观因素影响而只考虑主观因素影响的一种相对分数.在确立学生多科考试总成绩相对位次的应用方面(如招生、评优、评奖等),由于仅仅考虑孝生总成绩的相对高低,因此标准分数较原始卷面分数显得更为恰当、合理、客观、公正.     

论普通话水平测试焦虑心理及调节

普通话水平测试焦虑是应试人在测试准备阶段和测试过程中的心理紧张、担心、恐惧等在情绪上的反应。导致焦虑的原因主要有 :期望值太高 ,心理负荷过大 ;自信心和心理预防措施不足 ;知识技能及相关准备不充分。为提高测试成绩 ,减轻或排解过强焦虑 ,应试人要正确认识普通话水平测试 ,端正测试动机 ;提出适宜的等级目标 ;做好充分准备 ,形成良好的测试状态 ;掌握一些处理“怯场”的办法。     

关于英语口语能力测试信度的思考

测试信度是与效度同等重要的考试学理论。口试作为一种主观性考试 ,其信度评估一直制约口试的推广。本文运用美国语言学家奥勒 (JohnW .Oller;Jr)的“语用期待语法规则”理论 ,把口试作为一种交际性测试来研究 ,结合口试实践 ,分析影响口试信度的因素 ,以及提高口试信度的方式。     

中国高新技术产业税收优惠政策实证研究

税收优惠政策是各国税制中不可或缺的重要组成部分,也是政府调控经济的重要手段。中国高新技术企业的税收和费用负担水平、高新技术企业上缴的税外费用和税收的比例、高新技术企业在投产前八年的盈亏状况、现行的税收优惠政策实际功效、发展高新技术产业的税收与收费政策障碍等问题的实证研究表明,中国现行的税收优惠政策有些已不再适用,有些激励作用已明显减弱,有些已成为高新技术产业发展的障碍因素。因此,继续推进中国高新技术产业发展,必须有新的税收政策和具体的政策措施与改革思路。     

Statistical inference for start-up demonstration tests with rejection of units upon observing d failures

In this paper, we consider the statistical inference for the success probability in the case of start-up demonstration tests in which rejection of units is possible when a pre-fixed number of failures is observed before the required number of consecutive successes are achieved for acceptance of the unit. Since the expected value of the stopping time is not a monotone function of the unknown parameter, the method of moments is not useful in this situation. Therefore, we discuss two estimation methods for the success probability: (1) the maximum likelihood estimation (MLE) via the expectation-maximization (EM) algorithm and (2) Bayesian estimation with a beta prior. We examine the small-sample properties of the MLE and Bayesian estimator. Finally, we present an example to illustrate the method of inference discussed here.