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1.
成人高校目前人才培养与劳动力市场的关系模式,基本上可以归结为“对口”与“适应”两种取向。但是,无论取向何种模式,透过毕业生就业以及就业后的发展实际看,都各有利弊。因此,成人高校在人才培养的取向上,不能单纯追求或固守其中的某一种模式,而应根据社会主义市场经济发展和劳动力市场的需求,建立起多元化、多层次的人才培养模式。  相似文献   
2.
提出了一种基于小波变换的管理数据处理方法,把公司管理上的数据看成一个非平稳的时间序列,利用小渡函数将该时间序列分解到不同的频率通道上,然后将分解后的信号当作近似的平稳时间序列,用一些传统的统计方法进行预测,同时对中国足球彩票若干期的销售量数据进行了处理和预测,并将结果与实际销量以及用传统的AR模型的预测值进行了比较。  相似文献   
3.
通过2个月的运动元记忆训练,检验其对非体育专业学生元记忆水平和动作记忆成绩的影响.结果显示运动元记忆训练能显著提高大学生运动记忆策略和记忆监控水平;结果还表明训练能明显提高大学生的艺术体操和健美操动作记忆成绩(表现在动作数量上),而且艺术体操动作记忆的训练效应大于健美操.  相似文献   
4.
论工程训练与创新人才培养   总被引:7,自引:1,他引:6  
工程训练是重要的实践性教学环节 ,必须把工作重点转移到培养学生创新能力上来 ,创造有利于培养创新人才的环境 ,传授给学生丰富的创新知识基础 ,改革教学内容、教学方法、教学手段和考核办法 ,以保证培养创新人才的需要 ,并注意培养学生各种创新素质 ,鼓励学生创新 ,促进其创新能力的发展  相似文献   
5.
论述了少年儿童拳击运动身体训练的可行性及重要性,分析了少年儿童不同时期的生理特征及与之相适应的拳击运动身体训练方法手段的选择,可为少年儿童拳击运动的科学化训练提供理论依据。  相似文献   
6.
Olive Oil Consumption in Greece: A Microeconometric Analysis   总被引:2,自引:1,他引:1  
In this paper, the factors affecting at-home demand for three types of oils and fats in Greece, with emphasis on olive oil, are investigated using the linear approximation of the Almost Ideal Demand System and family budget survey data. To overcome the econometric problem created with the existence of zero expenditure, a generalization of the two-stage Heckman procedure is employed. In order to investigate the role of self-consumption, two different samples were used. The first includes all households; the second excludes those that acquire olive oil only from own production. According to the results, there are important differences in the first stage of the decision process between the two samples. Unlike the first stage, the second stage of the decision process found no important differences between the results for the two samples.  相似文献   
7.
The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SEΔ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SEΔ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SEΔ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
8.
A test of congruence among distance matrices is described. It tests the hypothesis that several matrices, containing different types of variables about the same objects, are congruent with one another, so they can be used jointly in statistical analysis. Raw data tables are turned into similarity or distance matrices prior to testing; they can then be compared to data that naturally come in the form of distance matrices. The proposed test can be seen as a generalization of the Mantel test of matrix correspondence to any number of distance matrices. This paper shows that the new test has the correct rate of Type I error and good power. Power increases as the number of objects and the number of congruent data matrices increase; power is higher when the total number of matrices in the study is smaller. To illustrate the method, the proposed test is used to test the hypothesis that matrices representing different types of organoleptic variables (colour, nose, body, palate and finish) in single‐malt Scotch whiskies are congruent.  相似文献   
9.
Maximum likelihood estimation and goodness-of-fit techniques are used within a competing risks framework to obtain maximum likelihood estimates of hazard, density, and survivor functions for randomly right-censored variables. Goodness-of- fit techniques are used to fit distributions to the crude lifetimes, which are used to obtain an estimate of the hazard function, which, in turn, is used to construct the survivor and density functions of the net lifetime of the variable of interest. If only one of the crude lifetimes can be adequately characterized by a parametric model, then semi-parametric estimates may be obtained using a maximum likelihood estimate of one crude lifetime and the empirical distribution function of the other. Simulation studies show that the survivor function estimates from crude lifetimes compare favourably with those given by the product-limit estimator when crude lifetimes are chosen correctly. Other advantages are discussed.  相似文献   
10.
Summary.  As a part of the EUREDIT project new methods to detect multivariate outliers in incomplete survey data have been developed. These methods are the first to work with sampling weights and to be able to cope with missing values. Two of these methods are presented here. The epidemic algorithm simulates the propagation of a disease through a population and uses extreme infection times to find outlying observations. Transformed rank correlations are robust estimates of the centre and the scatter of the data. They use a geometric transformation that is based on the rank correlation matrix. The estimates are used to define a Mahalanobis distance that reveals outliers. The two methods are applied to a small data set and to one of the evaluation data sets of the EUREDIT project.  相似文献   
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