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71.
高校科研平台评价与预测分析是促进科研工作健康高效发展的重要载体,但数据指标繁冗、逻辑关系复杂、影响因素众多等大大加剧了科研平台运行评价和预测难度。本文从大数据角度出发探索一种基于GCA-DEA-MSVC方法的高校科研平台评价预测方法。首先利用GCA方法从科研平台运行数据库中挖掘、提取出与评价结果密切相关的关键特征指标并进行分类构建特征指标库,然后利用DEA方法对特征指标库数据进行融合,提升数据质量构建相对效率指标库;最后,将特征指标库与相对效率指标库再次融合,基于改进的MSVC方法构建了高效的科研平台运行状态评价分类预测模型,并利用教育部重点实验室评价数据开展了实验研究,验证了所提方法的有效性。  相似文献   
72.
中国高龄老人生活自理能力纵向动态研究   总被引:4,自引:0,他引:4  
利用"中国老年健康长寿跟踪调查"1998年、2000年、2002年的跟踪数据分析中国高龄老人ADL的变动趋势及其影响因素。个体增长模型结果显示,高龄老人ADL状况随年龄增长出现了明显的下降趋势,ADL个体差异十分显著。个体之间的差异解释了ADL总差异的31.13%。经历三次追踪调查的高龄老人ADL均值较高,状况较好,下降速度较慢;基期具有3-4项残障的高龄老人,未来ADL下降最为迅速;基期ADL水平高的高龄老人,ADL下降较慢。从ADL的个体影响因素来看,对于基期ADL水平影响最大的变量是"年龄"、"疾病状况"以及"居住安排"等,而对观测期ADL变动速度影响最大的变量是"年龄"以及"过去是否经常从事体力劳动"等。  相似文献   
73.
This paper considers a class of summary measures of the dependence between a pair of failure time variables over a finite follow-up region. The class consists of measures that are weighted averages of local dependence measures, and includes the cross-ratio-measure and finite region version of Kendall's τ; recently proposed by the authors. Two new special cases are identified that can avoid the need to estimate the bivariate survivor function and that admit explicit variance estimators. Nonparametric estimators of such dependence measures are proposed and are shown to be consistent and asymptotically normal with variances that can be consistently estimated. Properties of selected estimators are evaluated in a simulation study, and the method is illustrated through an analysis of Australian Twin Study data.  相似文献   
74.
In sequential studies, formal interim analyses are usually restricted to a consideration of a single null hypothesis concerning a single parameter of interest. Valid frequentist methods of hypothesis testing and of point and interval estimation for the primary parameter have already been devised for use at the end of such a study. However, the completed data set may warrant a more detailed analysis, involving the estimation of parameters corresponding to effects that were not used to determine when to stop, and yet correlated with those that were. This paper describes methods for setting confidence intervals for secondary parameters in a way which provides the correct coverage probability in repeated frequentist realizations of the sequential design used. The method assumes that information accumulates on the primary and secondary parameters at proportional rates. This requirement will be valid in many potential applications, but only in limited situations in survival analysis.  相似文献   
75.
We consider the competing risks set-up. In many practical situations, the conditional probability of the cause of failure given the failure time is of direct interest. We propose to model the competing risks by the overall hazard rate and the conditional probabilities rather than the cause-specific hazards. We adopt a Bayesian smoothing approach for both quantities of interest. Illustrations are given at the end.  相似文献   
76.
This paper considers the estimation of Cobb-Douglas production functions using panel data covering a large sample of companies observed for a small number of time periods. GMM estimatorshave been found to produce large finite-sample biases when using the standard first-differenced estimator. These biases can be dramatically reduced by exploiting reasonable stationarity restrictions on the initial conditions process. Using data for a panel of R&Dperforming US manufacturing companies we find that the additional instruments used in our extended GMM estimator yield much more reasonable parameter estimates.  相似文献   
77.
论高校专业资料室在教改中的特点及服务   总被引:1,自引:0,他引:1  
本文从多方面对高校专业资料室的工作特点、内容及形式进行探讨 ,以使其在教改及科学研究中发挥更大的作用。  相似文献   
78.
鲁迅所辑的《古小说钩沉》主要涉及三国到南北朝时期的志怪小说,历来为文学界所重视,并作为中国小说发展史史料而被广泛引用。在民间佛教这一尚待开拓的研究领域,《古小说钩沉》为两晋南北朝的民间佛教研究提供了重要的史料。《古小说钩沉》的民间佛教突出灵验特色,在信仰、仪式、象征体系中形成了自己的特点。中国民间佛教的定型主要是在南北朝时期完成的。  相似文献   
79.
We evaluate the estimation performance of the Binary Dynamic Logit model for correlated ordinal variables (BDLCO model), and compare it to GEE and Ordinal Logistic Regression performance in terms of bias and Mean Absolute Percentage Error (MAPE) via Monte Carlo simulation. Our results indicate that when the proportional-odds assumption does not hold, the proposed BDLCO method is superior to existing models in estimating correlated ordinal data. Moreover, this method is flexible in terms of modeling dependence and allows unequal slopes for each category, and can be used to estimate an apple bloom data set where the proportional-odds assumption is violated. We also provide a function in R to implement BDLCO.  相似文献   
80.
In this paper, a new multivariate zero-inflated binomial (MZIB) distribution is proposed to analyse the correlated proportional data with excessive zeros. The distributional properties of purposed model are studied. The Fisher scoring algorithm and EM algorithm are given for the computation of estimates of parameters in the proposed MZIB model with/without covariates. The score tests and the likelihood ratio tests are derived for assessing both the zero-inflation and the equality of multiple binomial probabilities in correlated proportional data. A limited simulation study is performed to evaluate the performance of derived EM algorithms for the estimation of parameters in the model with/without covariates and to compare the nominal levels and powers of both score tests and likelihood ratio tests. The whitefly data is used to illustrate the proposed methodologies.  相似文献   
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