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1.
哪些研究问题需要用分层线性模型回答   总被引:6,自引:0,他引:6  
采用常规的回归分析或方差分析处理行为科学与社会科学研究中经常遇到的嵌套数据,不能满足独立观察的假定,得到的标准误差较小,导致I型错误扩大化,同时,也不利于对不同层次变量不同作用的探讨,分层线性则明确区分数据层次,通过对个体水平变量和组别水平变量的分层综合分析,避免了上述弊病,因而可对个体水平的变量进行更准确的预测和更合理的解释,通过实例介绍了将研究问题与分层线性模型有机结合的方法。  相似文献   
2.
通过100m跨栏跑的单元教学,施以不同的教学方法,观察学生完成技术动作的情况。运用单因素方差分析,经SAS软件检验,认为栏间四步技术是普通高校女生100m跨栏跑的合理技术。  相似文献   
3.
Since Cronbach's (1951) elaboration of α from its introduction by Guttman (1945), this coefficient has become ubiquitous in characterizing assessment instruments in education, psychology, and other social sciences. Also ubiquitous are caveats on the calculation and interpretation of this coefficient. This article summarizes a recent contribution (Andrich, 2015) on the use of coefficient α which complements these many caveats. It shows that in the presence of a simple bifactor structure of a scale where unique components of variance are homogeneous in magnitude, three components of variance and the common latent common correlation among the subscales can be calculated from the ratio of two calculations of α, one at the level of the items, the other at the level of the subscales. It was suggested that these two ready calculations and their interpretation, and the reporting of all four indices in the analysis of scales with a subscale structure, would reduce the misinterpretation of this coefficient. An illustrative example of the application of the calculations is also shown.  相似文献   
4.
介绍了一类有趣的离散型随机变量。它的均值和方差都是1,并由此得到了几个求和公式.而这几个公式的求和问题不论是用初等方法或分析方法都是比较困难的,但用概率的方法却比较容易解决.  相似文献   
5.
For the two-way factorial design in analysis of variance, the current article explicates and compares three methods for controlling the Type I error rate for all possible simple interaction contrasts following a statistically significant interaction, including a proposed modification to the Bonferroni procedure that increases the power of statistical tests for deconstructing interaction effects when they are of primary substantive interest. Results indicate the general superiority of the modified Bonferroni procedure over Scheffé and Roy-type procedures, where the Bonferroni and Scheffé procedures have been modified to accommodate the logical implications of a false omnibus interaction null hypothesis. An applied example is provided and considerations for applied researchers are offered.  相似文献   
6.
文章分析了在一个角度和一个三角形中进行后方交会时最佳点位的规律,指出某些规程中有关后方交会问题的不足之处.  相似文献   
7.
This article outlines an interval estimation procedure that can be used in a 3-level setting to evaluate the proportion of outcome variance attributable to the second level of clustering. The method is useful for examining the necessity of including a possibly omitted intermediate level of nesting in analyses of data from a multilevel study, and represents an informative addendum to current statistical tests of second-level variance. The approach is developed within the framework of latent variable modeling and can be used as an aid in the process of choosing between 2-level and 3-level models in a hierarchical design. The discussed procedure is illustrated with an empirical example.  相似文献   
8.
招呼语是言语交际活动的重要组成部分,随着人们文化水平的不断提高,招呼语呈现出时尚化、现代化的特点,与中国传统的招呼语相比,现代招呼语在话题选择和句式选择方面具有开放性、多样性、变异性特点。现代社会,人们的交际活动日益丰富多彩,使用恰当、得体的招呼语显得特别重要。交际活动中,招呼语要受话语构建、话语理解、话语角色、语言环境、民族文化心理等因素的制约和影响。  相似文献   
9.
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits (fruit length and fruit perimeter) in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage (1-12 d after flowering) for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage (13-60 datter flowering). The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage.  相似文献   
10.
基于向量自回归模型(VAR)的脉冲响应函数和方差分解,分析我国高校扩招后高等教育投资对我国就业结构调整的影响。研究表明:我国高校扩招后的高等教育投资对我国就业结构优化的作用有限;三次产业就业人员对来自高等教育一个标准差信息扰动的冲击,脉冲响应曲线有差异;高等教育投资扰动对三次产业就业人员波动的解释力都比较大,但是对第二...  相似文献   
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