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951.
An explicit form of confidence intervals for the treatment effect in random effects meta-analysis model obtained from Harville–Jeske–Kenward–Roger approach is given. These restricted likelihood based intervals are compared to alternative procedures commonly used in collaborative studies when the number of participants is small and study-specific variances are heterogeneous. Monte Carlo simulation experiments show that the former intervals have quite conservative coverage probabilities and favor the latter intervals. 相似文献
952.
Biljana Stosic Nebojsa Zakic Nedeljko Zivkovic 《Innovation: The European Journal of Social Science Research》2016,29(2):177-191
This paper addresses a particular innovation projects category, that is, eco-innovation, in line with the fact that a lot of research has been recently carried out in this area, due to increasing attention. Eco-innovation projects are related to development and introducing the new products, processes and services that reduce the overall negative impact on the environment, putting the business and innovation together to create sustainable solutions. The aim of our research is developing a model for prioritization of the most frequent eco-innovation projects in the recycling field. It should be one of the key challenges for national economies as it happens to be one of the current priorities and burning issues for the European Commission (Horizon 2020, CIP, COSME, etc.), giving the proposed model framework. The ranking has been established with regard to common national economy benefits defined through identified criteria, by applying the well-known analytic hierarchy process method of multi-criteria decision-making. 相似文献
953.
周浩华 《吉林工程技术师范学院学报》2014,(1):68-70
本文概述了产业竞争力的基本内涵以及波特的钻石模型,基于SWOT对杭州动漫产业竞争力进行了详细的定性分析,并运用DEA模型对动漫产业竞争力进行了相应的评价,从多个角度为杭州动漫产业竞争力的提升提出了对策建议。 相似文献
954.
《Omega》2014
Electricity consumption forecasting has been always playing a vital role in power system management and planning. Inaccurate prediction may cause wastes of scarce energy resource or electricity shortages. However, forecasting electricity consumption has proven to be a challenging task due to various unstable factors. Especially, China is undergoing a period of economic transition, which highlights this difficulty. This paper proposes a time-varying-weight combining method, i.e. High-order Markov chain based Time-varying Weighted Average (HM-TWA) method to predict the monthly electricity consumption in China. HM-TWA first calculates the in-sample time-varying combining weights by quadratic programming for the individual forecasts. Then it predicts the out-of-sample time-varying adaptive weights through extrapolating these in-sample weights using a high-order Markov chain model. Finally, the combined forecasts can be obtained. In addition, to ensure that the sample data have the same properties as the required forecasts, a reasonable multi-step-ahead forecasting scheme is designed for HM-TWA. The out-of-sample forecasting performance evaluation shows that HM-TWA outperforms the component models and traditional combining methods, and its effectiveness is further verified by comparing it with some other existing models. 相似文献
955.
In this study, we examined the dynamics of the perception of “dislike” ties (reputational dislike) among adolescents within the contexts of friendship, perceived popularity, substance use, and Facebook use. Survey data were collected from a longitudinal sample of 238 adolescents from the 11th and 12th grades in one California high school. We estimated stochastic actor-based network dynamic models, using reports of reputational dislike, friendships, and perceived popularity, to identify factors associated with the maintenance and generation reputational dislike ties. The results showed that high-status adolescents and more frequent Facebook users tended to become perceived as or stay disliked by their peers over time. There was a tendency for friendships to promote the creation and maintenance of reputational disliking but not vice versa. Adolescents tended to perceive others as disliked when their friends also perceived them as disliked. There was no evidence that either cigarette smoking or drinking alcohol affected reputational dislike dynamics. This study highlights the important role that the hierarchical peer system, online peer context, and friendships play in driving information diffusion of negative peer relations among adolescents. 相似文献
956.
This paper deals with the study of some probabilistic and statistical properties of a periodic integer-valued diagonal bilinear model. The existence of a periodically strict stationary integer-valued process is shown. Sufficient conditions for the periodically stationary, both in the first and second orders, are established. The closed-forms of the mean and the second moment are obtained. The closed-form of the periodic autocovariance function is established. The Yule–Walker estimations of the underlying parameters are obtained. A simulation study is provided. 相似文献
957.
958.
Nina Meinel 《AStA Advances in Statistical Analysis》2009,93(2):159-174
For multivariate probit models, Spiess and Tutz suggest three alternative performance measures, which are all based on the
decomposition of the variation. The multivariate probit model can be seen as a special case of the discrete copula model.
This paper proposes some new measures based on the value of the likelihood function and the prediction-realization table.
In addition, it generalizes the measures from Spiess and Tutz for the discrete copula model. Results of a simulation study
designed to compare the different measures in various situations are presented. 相似文献
959.
王素娟 《山东大学学报(哲学社会科学版)》2012,(4):81-88
随着我国经济的快速发展,过度劳动的现象日益突出,过度劳动的后果是相关人员生活、工作、人际关系等质量下降,由此导致组织绩效下降。通过调研和实证,以JDR模型为分析基础,将过度劳动的形成要素归纳为基础变量、直接变量和间接变量三大维度,在此基础上构建了过度劳动的形成机制模型,并通过工作压力度这个中介变量揭示了三大变量之间的关系及过度劳动的动态形成机理。结合国情,建立了对过度劳动进行有效管理的模型,从两大系统和六个层面提出对过度劳动进行动态化、体系化的预防与应对策略。 相似文献
960.
The problem of updating discriminant functions estimated from inverse Gaussian populations is investigated in situations when the additional observations are mixed (unclassified) or classified. In each case two types of discriminant functions, linear and quadratic, are considered. Using simulation experiments the performance of the updating procedures is evaluated by means of relative efficiencies. 相似文献