基于多智能体的复杂信息系统开发方法研究

提出一种将组织学与多智能主体技术相结合建造复杂信息系统的开发方法. 该方法的基 本思想是首先将复杂信息系统看成一个多主体组织, 依据组织学原理分析多主体系统组织特 性, 建立多主体组织模型, 从而形成多主体系统宏观结构和功能需求的严格规范; 其次, 根据现 有技术和可用资源确定承担各类组织职能的多个主体, 由此确定了各主体的职责和粒度; 然 后, 依据组织模型, 采用信念2愿望2意图(BD I) 结构设计各类主体的概念模型, 为系统的机上实 现建立清晰的可操作的开发模式; 最后, 将所设计的概念模型在协同工作平台(MBO S) 上编程 实现, 快速获得复杂信息系统的原型系     

To be or not to be valid in testing the significance of the slope in simple quantitative linear models with autocorrelated errors

In this article, the validity of procedures for testing the significance of the slope in quantitative linear models with one explanatory variable and first-order autoregressive [AR(1)] errors is analyzed in a Monte Carlo study conducted in the time domain. Two cases are considered for the regressor: fixed and trended versus random and AR(1). In addition to the classical t -test using the Ordinary Least Squares (OLS) estimator of the slope and its standard error, we consider seven t -tests with n-2\,\hbox{df} built on the Generalized Least Squares (GLS) estimator or an estimated GLS estimator, three variants of the classical t -test with different variances of the OLS estimator, two asymptotic tests built on the Maximum Likelihood (ML) estimator, the F -test for fixed effects based on the Restricted Maximum Likelihood (REML) estimator in the mixed-model approach, two t -tests with n - 2 df based on first differences (FD) and first-difference ratios (FDR), and four modified t -tests using various corrections of the number of degrees of freedom. The FDR t -test, the REML F -test and the modified t -test using Dutilleul's effective sample size are the most valid among the testing procedures that do not assume the complete knowledge of the covariance matrix of the errors. However, modified t -tests are not applicable and the FDR t -test suffers from a lack of power when the regressor is fixed and trended ( i.e. , FDR is the same as FD in this case when observations are equally spaced), whereas the REML algorithm fails to converge at small sample sizes. The classical t -test is valid when the regressor is fixed and trended and autocorrelation among errors is predominantly negative, and when the regressor is random and AR(1), like the errors, and autocorrelation is moderately negative or positive. We discuss the results graphically, in terms of the circularity condition defined in repeated measures ANOVA and of the effective sample size used in correlation analysis with autocorrelated sample data. An example with environmental data is presented.     

A Unified Way to Represent and Compute the Cumulative Distribution Function for Noncentral t,F, and χ2

This short article shows an unified approach to representing and computing the cumulative distribution function for noncentral t, F, and χ². Unlike the existing algorithms, which involve different expansion and/or recurrence, the new approach consistently represents all the three noncentral cumulative distribution functions as the integral of the normal cumulative distribution function and χ² density function.     

A note on approximate confidence limits for the negative binomial model

Four methods of approximating confidence limits for the single negative binomial parameter, P, are outlined and an empirical study is presented. Some remarks on prediction intervals are also included.     

Modified maximum likelihood estimator under the Jones and Faddy's skew t-error distribution for censored regression model

It is well-known that classical Tobit estimator of the parameters of the censored regression (CR) model is inefficient in case of non-normal error terms. In this paper, we propose to use the modified maximum likelihood (MML) estimator under the Jones and Faddy''s skew t-error distribution, which covers a wide range of skew and symmetric distributions, for the CR model. The MML estimators, providing an alternative to the Tobit estimator, are explicitly expressed and they are asymptotically equivalent to the maximum likelihood estimator. A simulation study is conducted to compare the efficiencies of the MML estimators with the classical estimators such as the ordinary least squares, Tobit, censored least absolute deviations and symmetrically trimmed least squares estimators. The results of the simulation study show that the MML estimators work well among the others with respect to the root mean square error criterion for the CR model. A real life example is also provided to show the suitability of the MML methodology.     

联合采用吸附树脂与离子交换树脂提取河豚毒素

本文研究了联合采用吸附树脂D＋D101与弱酸性阳离子交换树脂D152提取河豚毒素的方法，通过动物中毒实验表明，本方法能有效地从河豚内脏中分离提取出河豚毒素，并改进了除蛋白质的方法，效果良好。     

“科研育人”论纲

关于高校的育人方式,目前理论界和教育工作者普遍认为,主要有“教学育人”、“管理育人”和“服务育人”三种方式.在知识经济时代,社会更需要具有创新精神和创新能力的人才.因此,“科研育人”的提出,既是时代的呼唤,又是高校实施素质教育的要求.科研的育人功能,主要体现在如下几个方面1.激发学生的创造力,培养学生的创新精神;2.影响学生未来的学术和职业发展;3.促进学生的个性发展;4.增强学生识假辨伪、反对迷信愚昧的能力;5.培养学生的良好学风;6.培养学生的完整人格.国内外的一些高校已在科研育人方面积累了许多经验,值得学习.“科研育人”应始终贯穿于教学过程之中.充分发挥科研的育人功能,需要学校、社会为其创造必要的条件,应当建立健全学生的全面的评价指标体系和激励机制.     

Single-stage sampling procedure of the t best populations under heteroscedasticity

Given k( ? 3) independent normal populations with unknown means and unknown and unequal variances, a single-stage sampling procedure to select the best t out of k populations is proposed and the procedure is completely independent of the unknown means and the unknown variances. For various combinations of k and probability requirement, tables of procedure parameters are provided for practitioners.     

Attitude strength moderates adverse effects to questionnaire design

ABSTRACT

The presentation and visual design of the “don’t know” category in rating scales on respondents’ behavior may have ambivalent effects. The hypothesis is that attitude strength toward the topic influences the respondents’ sensitivity to the graphical design of the scale. A paper-and-pencil questionnaire conducted among 307 German university students contained an experimental variation of the presentation of a “don’t know” category and its visual design. A multinomial logistic regression shows that presenting a “don’t know” category drives respondents toward extreme categories. The visual design of the “don’t know” category influences the distribution of responses, all the more that the respondents’ attitudes toward the item topic are weak.     

On gart's test for interaction of second order

Gart (1972) ottered a Statistic on testing the hypothesis of no second-order interaction in a 2×s×t contingency table. The statistic was tn be used as an asymptotic chi-square with (s-1) (t-1) degrees of freedom. We show that this statistic suiters from the drawback that unless certain side conditions hold, the statistic would reject the null hypothesis with probability approaching one asymptotically even in the null case. Hence the statistic is not strictly valid for the hypothesis for which it was intended.