大小班结合的多媒体教学模式之实证研究

在从理论上探讨大小班结合的多媒体教学模式可行性的基础上,以三峡大学200名学生为研究对象,对该校一年半来采用该模式的授课效果进行了实证性研究。实验结果表明,大学英语采用大小班结合的多媒体教学模式比传统教学模式更有利于培养学生的综合运用能力,尤其是学生的听说能力。     

Implied Preference for Seismic Design Level and Earthquake Insurance

Seismic risk can be reduced by implementing newly developed seismic provisions in design codes. Furthermore, financial protection or enhanced utility and happiness for stakeholders could be gained through the purchase of earthquake insurance. If this is not so, there would be no market for such insurance. However, perceived benefit associated with insurance is not universally shared by stakeholders partly due to their diverse risk attitudes. This study investigates the implied seismic design preference with insurance options for decisionmakers of bounded rationality whose preferences could be adequately represented by the cumulative prospect theory (CPT). The investigation is focused on assessing the sensitivity of the implied seismic design preference with insurance options to model parameters of the CPT and to fair and unfair insurance arrangements. Numerical results suggest that human cognitive limitation and risk perception can affect the implied seismic design preference by the CPT significantly. The mandatory purchase of fair insurance will lead the implied seismic design preference to the optimum design level that is dictated by the minimum expected lifecycle cost rule. Unfair insurance decreases the expected gain as well as its associated variability, which is preferred by risk-averse decisionmakers. The obtained results of the implied preference for the combination of the seismic design level and insurance option suggest that property owners, financial institutions, and municipalities can take advantage of affordable insurance to establish successful seismic risk management strategies.     

论英语语言课程设计中的需求分析

界定需求要从目标和目的两个方面进行,这两个方面是我们发展测试、材料、教学活动、评价策略的基础。因此需求分析是语言课程建设不可分割的一部分。本文重点介绍了英语语言课程设计中需求分析的方法及步骤。目的在于强调需求分析的重要性,以及需求分析对于教师改进教学方法、提高教学效果、提高学生学习的主动性和积极性的重要意义。     

新世纪"模具设计与制造"专科专业课程体系改革的研究

文章从社会和科技的发展出发,对模具专业课程体系改革的相关问题进行了研究,拟定的改革方案已付诸实施,并已取得初步成果.     

Non-ignorable missing covariate data in survival analysis: a case-study of an International Breast Cancer Study Group trial

Summary.  Non-ignorable missing data, a serious problem in both clinical trials and observational studies, can lead to biased inferences. Quality-of-life measures have become increasingly popular in clinical trials. However, these measures are often incompletely observed, and investigators may suspect that missing quality-of-life data are likely to be non-ignorable. Although several recent references have addressed missing covariates in survival analysis, they all required the assumption that missingness is at random or that all covariates are discrete. We present a method for estimating the parameters in the Cox proportional hazards model when missing covariates may be non-ignorable and continuous or discrete. Our method is useful in reducing the bias and improving efficiency in the presence of missing data. The methodology clearly specifies assumptions about the missing data mechanism and, through sensitivity analysis, helps investigators to understand the potential effect of missing data on study results.     

Merging information for semiparametric density estimation

Summary.  The density ratio model specifies that the likelihood ratio of m −1 probability density functions with respect to the m th is of known parametric form without reference to any parametric model. We study the semiparametric inference problem that is related to the density ratio model by appealing to the methodology of empirical likelihood. The combined data from all the samples leads to more efficient kernel density estimators for the unknown distributions. We adopt variants of well-established techniques to choose the smoothing parameter for the density estimators proposed.     

Assessing goodness-of-fit of categorical regression models based on case-control data

Demonstrated equivalence between a categorical regression model based on case‐control data and an I‐sample semiparametric selection bias model leads to a new goodness‐of‐fit test. The proposed test statistic is an extension of an existing Kolmogorov–Smirnov‐type statistic and is the weighted average of the absolute differences between two estimated distribution functions in each response category. The paper establishes an optimal property for the maximum semiparametric likelihood estimator of the parameters in the I‐sample semiparametric selection bias model. It also presents a bootstrap procedure, some simulation results and an analysis of two real datasets.     

Robustness of a Class of Partial Diallel Cross Designs to the Unavailability of a Complete Block of Observations

Complete and partial diallel cross designs are examined as to their construction and robustness against the loss of a block of observations. A simple generalized inverse is found for the information matrix of the line effects, which allows evaluation of expressions for the variances of the line-effect differences with and without the missing block. A-efficiencies, based on average variances of the elementary contrasts of the line-effects, suggest that these designs are fairly robust. The loss of efficiency is generally less than 10%, but it is shown that specific comparisons might suffer a loss of efficiency of as much as 40%.     

论设计中的符号学运用

基于对符号学理论的把握,对设计中符号的运用进行分析与探讨。设计中符号一般具有可识、通适、限制和特殊的特点。同时,设计手法中的符号使用也可分为象征、相关、相似等三种形式。总之,对符号学的研究有助于设计师在处理人、作品与环境之间关系的同时较好地完成设计过程。     

文化科学的意蕴：意义理解和价值判断——马克斯·韦伯《社会科学方法论》对人文社会科学研究的启示

《社会科学方法论》是马克斯·韦伯方法论著述的代表作，书中突出了韦伯方法论学说的主要概念。文章着力探究了韦伯方法论学说的思维元点和维度方法，并通过理解这些概念和思想所处的理论境域，分析和讨论了在此基础上其所涉及的一般性问题，揭示马克斯·韦伯《社会科学方法论》对我们进行人文社会科学研究的意义和价值。