参数假设检验教学中的几个问题

在概率统计教学的基础上,对参数假设检验教学中出现的学生难于理解的几个问题做了系统的总结,主要包括决策的依据,拒绝域的选择以及决策可靠性的判断,其中对做出"接受零假设"决策的可靠性给出了解释。     

货币政策与资本市场关系的理论溯源

货币政策与资本市场之间的关系,其深刻的理论渊源可以从货币数量理论和有效市场理论的有关论述中探寻。这些理论对于货币政策在资本市场预测效力上存在争论,经济学家对这两种理论的维护和相互融通方面做出了重要贡献。     

对理性人假设批判的批判

理性人假设是经济学大厦的基石之一.自其提出之日,就遭到学者广泛而激烈地批评,但似乎并没有妨碍以理性人假设为基础的个人主义分析方法攻城掠地,形成目前庞大的经济学帝国主义,直至目前,也没有看出它放慢侵略的步伐.在表象背后,必然有对理性人假设的现实需求,必然存在其内在合理性和重要价值性:首先,理性人假设是一种方法论逻辑,为科学研究所必须;其次,理性人假设是追求最大化,而非实现了最大化,梦想能否实现是受制度、技术、文化等现实的约束;再次,相比其他人性假设更接近现实,它为社会治理提供一种可能的进路;最后,它是激励约束制度设计的前提.     

Robust pairwise multiple comparisons under short-tailed symmetric distributions

In one-way ANOVA, most of the pairwise multiple comparison procedures depend on normality assumption of errors. In practice, errors have non-normal distributions so frequently. Therefore, it is very important to develop robust estimators of location and the associated variance under non-normality. In this paper, we consider the estimation of one-way ANOVA model parameters to make pairwise multiple comparisons under short-tailed symmetric (STS) distribution. The classical least squares method is neither efficient nor robust and maximum likelihood estimation technique is problematic in this situation. Modified maximum likelihood (MML) estimation technique gives the opportunity to estimate model parameters in closed forms under non-normal distributions. Hence, the use of MML estimators in the test statistic is proposed for pairwise multiple comparisons under STS distribution. The efficiency and power comparisons of the test statistic based on sample mean, trimmed mean, wave and MML estimators are given and the robustness of the test obtained using these estimators under plausible alternatives and inlier model are examined. It is demonstrated that the test statistic based on MML estimators is efficient and robust and the corresponding test is more powerful and having smallest Type I error.     

科学公理:基本概念和基本假设

科学公理亦称科学观念,它是科学理论的逻辑前提或概念框架.本文论述了科学公理的两大范畴即基本概念和基本假设的涵义和形成.     

On concurrence of several linear regressions and applications to problems of enzyme kinetics

In comparing several regressions E(y_ij) =α_i + β_ix_ij i = 1, 2, ..., k, j = 1,2, ..., n_i, researchers are generally interested in the following five problems: whether they have (1) equal slope, (2) equal intercept, (3) coincidence, (4) common intersection on X-axis, and (5) common intersection on (X,Y) - plane. Problems (1) - (3) can be put into the framework of the general linear hypothesis and the F-test can be used. However, problems (4) and (5) cannot be put into the general linear hypothesis because they are ratios of parameters. Hence, in this paper we consider the generalized likelihood ratio test for hypothesis testing. An application to an enzyme kinetics problem in Aniline Metabolism is demonstrated     

Conducting research using web-based questionnaires: Practical,methodological, and ethical considerations

The use of the internet for social science research is becoming increasingly common. This paper outlines practical, methodological and ethical issues for researchers to consider when using web-based questionnaires. This is illustrated by consideration of the authors' own experience of conducting a study into the phenomenon of self-harm.     

互动假说的建立及其对二语习得的启示

回顾互动假说理论的提出,阐述其理论来源,并结合国内学者的研究成果说明互动对二语习得的作用,同时指出当前中国外语教育存在的问题,最后有针对性地为我国的外语教学和学习提出一些建议。     

A simulation tool for modeling the influence of anatomy on information flow using discrete integrate and fire neurons

There are theories on brain functionality that can only be tested in very large models. In this work, a simulation model appropriate for working with large number of neurons was developed, and Information Theory measuring tools were designed to monitor the flow of information in such large networks. The model’s simulator can handle up to one million neurons in its current implementation by using a discretized version of the Lapicque integrate and fire neuron instead of interacting differential equations. A modular structure facilitates the setting of parameters of the neurons, networks, time and most importantly, architectural changes. Applications of this research are demonstrated by testing architectures in terms of mutual information. We present some preliminary architectural results showing that adding a virtual analogue to white matter called “jumps” to a simple representation of cortex results in: (1) an increase in the rate of mutual information flow, corresponding to the “bias” or “priming” hypothesis; thereby giving a possible explanation of the high speed response to stimuli in complex networks. (2) An increase in the stability of response of the network; i.e. a system with “jumps” is a more reliable machine. This also has an effect on the potential speed of response.