语言测试评估中的信度指标及其获取方法

信度指的是测验结果的一致性程度或者可靠性程度,主要有重测信度、折半信度、复本信度、布郎校正公式和克隆巴赫提出的a系数等。信度指标的获取方法主要有:用Spearm an-B row n P rophecy Form u la计算折半信度;用克朗巴赫(C ronbach)的a系数估算信度;用库德.理查逊21(K uder R ichardson form u la 21)公式计算信度;用库德.理查逊20(K uder R ichardson form u la20)公式计算信度系数。分析和研究信度的计算方法,理解信度的含义,正确运用信度的概念,对提高语言测试的质量,改进语言测试设计十分重要。     

中国外贸管理法的范式转换

在WTO新语境中,为积极参与、有效利用多边贸易体制,分享国际贸易增长与世界经济发展的成果,我国有必要从如下方面实现外贸管理法的范式转换:法律政策方面,实现从自由贸易到自由贸易与公平贸易相结合的转换;法律功能方面,实现从防御型立法到防御与进取型立法相结合的转换;法律价值方面,实现从"以政府为导向"到"以贸易参与人为导向"的转换;纠纷解决方面,实现从"以规则为导向"到"以规则为导向"与"以解决问题为导向"相结合的转换。     

Semiparametric Time-Varying Coefficients Regression Model for Longitudinal Data

Abstract.  In this paper, we consider a semiparametric time-varying coefficients regression model where the influences of some covariates vary non-parametrically with time while the effects of the remaining covariates follow certain parametric functions of time. The weighted least squares type estimators for the unknown parameters of the parametric coefficient functions as well as the estimators for the non-parametric coefficient functions are developed. We show that the kernel smoothing that avoids modelling of the sampling times is asymptotically more efficient than a single nearest neighbour smoothing that depends on the estimation of the sampling model. The asymptotic optimal bandwidth is also derived. A hypothesis testing procedure is proposed to test whether some covariate effects follow certain parametric forms. Simulation studies are conducted to compare the finite sample performances of the kernel neighbourhood smoothing and the single nearest neighbour smoothing and to check the empirical sizes and powers of the proposed testing procedures. An application to a data set from an AIDS clinical trial study is provided for illustration.     

高中英语新教材的应用呼唤交际式语言测试

高中英语新教材的应用,使得测试手段的改革势在必行.新教材与目前测试手段的矛盾日益突出,使得交际式语言测试的运用成为必然.科学地运用交际式语言测试,能对英语教学产生较好的反拨作用,从而提高高中英语教学质量.     

假设检验的一个常见误区

文章通过对假设检验的一个常见错误进行了理论分析,指出假设检验的方法只能在一定情况下否定原假设而不能肯定原假设,并提出了设定原假设和备择假设的正确而简明的方法。     

当今智力测验面临的问题与争论

智力测验争论的焦点是测验的有效性和公平性。多元智力理论就是为解决这些问题而产生的。但这些争议是由于人们的一些错误观念而产生的 ,而多元智力理论并不能从根本上消除这些争议。     

Comparison of Separable Components in Different Samples

Abstract.  Imagine we have two different samples and are interested in doing semi- or non-parametric regression analysis in each of them, possibly on the same model. In this paper, we consider the problem of testing whether a specific covariate has different impacts on the regression curve in these two samples. We compare the regression curves of different samples but are interested in specific differences instead of testing for equality of the whole regression function. Our procedure does allow for random designs, different sample sizes, different variance functions, different sets of regressors with different impact functions, etc. As we use the marginal integration approach, this method can be applied to any strong, weak or latent separable model as well as to additive interaction models to compare the lower dimensional separable components between the different samples. Thus, in the case of having separable models, our procedure includes the possibility of comparing the whole regression curves, thereby avoiding the curse of dimensionality. It is shown that bootstrap fails in theory and practice. Therefore, we propose a subsampling procedure with automatic choice of subsample size. We present a complete asymptotic theory and an extensive simulation study.     

Two-stage U-statistics for Hypothesis Testing

Abstract.  A U -statistic is not easy to apply or cannot be applied in hypothesis testing when it is degenerate or has an indeterminate degeneracy under the null hypothesis. A class of two-stage U -statistics (TU-statistics) is proposed to remedy these drawbacks. Both the asymptotic distributions under the null and the alternative of TU-statistics are shown to have simple forms. When the degeneracy is indeterminate, the Pitman asymptotic relative efficiency of a TU-statistic dominates that of the incomplete U -statistics. If the kernel is degenerate under the null hypothesis but non-degenerate under the alternative, a TU-statistic is proved to be more powerful than its corresponding U -statistic. Applications to testing independence of paired angles in ecology and marine biology are given. Finally, a simulation study shows that a TU-statistic is more powerful than its corresponding incomplete U -statistic in almost all cases under two settings.     

Empirical likelihood tests for two‐sample problems via nonparametric density estimation

The authors study the problem of testing whether two populations have the same law by comparing kernel estimators of the two density functions. The proposed test statistic is based on a local empirical likelihood approach. They obtain the asymptotic distribution of the test statistic and propose a bootstrap approximation to calibrate the test. A simulation study is carried out in which the proposed method is compared with two competitors, and a procedure to select the bandwidth parameter is studied. The proposed test can be extended to more than two samples and to multivariate distributions.     

‘Wallbanking’, innovativeness and computer attitudes: 25–40-year-old ATM-users on the spot

Attitudes towards ‘wallbanking’ (making use of banking services through an Automated Teller Machine (ATM)) and self-reported frequency of wallbanking have been related to attitudes towards innovations and towards computers. The investigation also included the perception of advantages as well as disadvantages of wallbanking, factors that determine one's choice of a bank, man-machine problems related to the use of an ATM, and demographic factors. Using a sample of 201 respondents in the age range of 25 to 40 years, structural equation modeling revealed that wallbanking attitudes have a major influence on the frequency of using ATMs. The innovativeness attitude ‘New is wasteful’ also showed a clear negative link with the frequency of wallbanking. On the other hand, the relationship between computer attitudes and the frequency of using ATMs had to be rejected. Income and education proved to have an indirect link with the frequency of wallbanking, which refines other research findings. These results may reflect specific financial management characteristics of the age group under investigation.