高校"树人"的历史责任

高校承担着培育“四有”新人的历史责任。为此 ,高等教育必须坚持党的教育方针不动摇 ,与时俱进 ,迎接挑战 ,切实加强和改进新时期大学生思想政治教育工作     

Martingale generalizations and preservation of martingale properties

This article investigates circumstances under which seven important martingale properties are preserved by the following six martingale generalizations: quasimartingales, amarts, martingales in the limit, games fairer with time, progressive martingales, and eventual martingales.     

略论“竹林玄谈”的社会本位品格与时代价值

以嵇康、阮籍思想为代表的"竹林玄谈",上承"正始玄风",下启"中朝清谈",开创了一条颇富特色的儒道互补之路.处于魏晋交替时代白色恐怖中生息的竹林玄谈,特异的政治历史背景赋予了其突出的社会本位品格.竹林玄谈在表面旷达风流的同时流露了其独特的社会忧患意识和社会批判精神,它塑造了众多高洁俊烈、风神独秀的一代名士.同时也在"越名教而任自然"的呼声中展现出了其独特的时代价值并千古流传.     

学业成绩高、低分中学生时间管理倾向特点的研究

本研究的目的是探讨学业成绩高、低分中学生时间管理倾向的特点。采用黄希庭、张志杰编制的青少年时间管理倾向量表对重庆市 6 36名中学生进行问卷调查 ,两次调查结果表明 :学业成绩高、低分中学生在时间价值感、时间监控观、时间效能感及时间管理倾向量表总分上的差异均显著 ,高分组学生得分高于低分组学生 ;时间管理倾向量表总分、时间监控观及时间效能感上的年级效应亦显著     

青年学生时间洞察力结构的初步探讨

通过文献分析和开放式问卷调查,初步构建了青少年时间洞察力的理论结构.探索性因素分析表明:该研究所构建的时间洞察力结构比较合理,可以分为过去时间洞察力、现在时间洞察力和未来时间洞察力三个维度,每个维度下又包含相应的几个因素.     

Regression Analysis of Restricted Mean Survival Time Based on Pseudo-Observations

Regression models for survival data are often specified from the hazard function while classical regression analysis of quantitative outcomes focuses on the mean value (possibly after suitable transformations). Methods for regression analysis of mean survival time and the related quantity, the restricted mean survival time, are reviewed and compared to a method based on pseudo-observations. Both Monte Carlo simulations and two real data sets are studied. It is concluded that while existing methods may be superior for analysis of the mean, pseudo-observations seem well suited when the restricted mean is studied.     

Choice of Parametric Accelerated Life and Proportional Hazards Models for Survival Data: Asymptotic Results

We discuss the impact of misspecifying fully parametric proportional hazards and accelerated life models. For the uncensored case, misspecified accelerated life models give asymptotically unbiased estimates of covariate effect, but the shape and scale parameters depend on the misspecification. The covariate, shape and scale parameters differ in the censored case. Parametric proportional hazards models do not have a sound justification for general use: estimates from misspecified models can be very biased, and misleading results for the shape of the hazard function can arise. Misspecified survival functions are more biased at the extremes than the centre. Asymptotic and first order results are compared. If a model is misspecified, the size of Wald tests will be underestimated. Use of the sandwich estimator of standard error gives tests of the correct size, but misspecification leads to a loss of power. Accelerated life models are more robust to misspecification because of their log-linear form. In preliminary data analysis, practitioners should investigate proportional hazards and accelerated life models; software is readily available for several such models.     

Semiparametric Inference Methods for General Time Scale Models

In this paper we consider semiparametric inference methods for the time scale parameters in general time scale models (Oakes, 1995, Duchesne and Lawless, 2000). We use the results of Robins and Tsiatis (1992) and Lin and Ying (1995) to derive a rank-based estimator that is more efficient and robust than the traditional minimum coefficient of variation (min CV) estimator of Kordonsky and Gerstbakh (1993) for many underlying models. Moreover, our estimator can readily handle censored samples, which is not the case with the min CV method.     

Perfect simulation for correlated Poisson random variables conditioned to be positive

In this paper we present a perfect simulation method for obtaining perfect samples from collections of correlated Poisson random variables conditioned to be positive. We show how to use this method to produce a perfect sample from a Boolean model conditioned to cover a set of points: in W.S. Kendall and E. Thönnes (Pattern Recognition 32(9): 1569–1586, 1999), this special case was treated in a more complicated way. The method is applied to several simple examples where exact calculations can be made, so as to check correctness of the program using ²-tests, and some small-scale experiments are carried out to explore the behaviour of the conditioned Boolean model.     

货币政策规则的理论发展与启示

货币政策规则(尤其是"泰勒规则")自被提出以来,就深受关注,并在与"相机抉择"的政策决策原则的交锋中不断得到发展。现在的货币政策规则不再局限于货币当局设定固定的货币工具变量的狭隘涵义,而是指货币政策行为的一种指令性的向导,具体包括工具规则与目标规则。经济学家相信,与相机决策相比,规则性的政策能有效减少货币政策的动态不一致性。但是,现阶段在中国建立货币政策规则,尤其是实行通货膨胀目标规则的货币政策的条件并不成熟,而加快金融、财政和计划体制的改革,提高中央银行的独立性,增强政策的透明度,努力提高央行货币政策的一致性的信誉,则是我国的当务之急。