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51.
外商直接投资影响因素的偏最小二乘回归建模分析   总被引:14,自引:0,他引:14  
改革开放的20多年来,我国的外商直接投资逐年增加,对我国经济的快速发展发挥了重要的作用。而影响外商直接投资的因素有很多,不同的因素变量之间往往存在多重共线性或近似多重共线性关系,使得分析问题的难度加大。本文运用新型的多元统计数据分析方法——偏最小二乘(PLS)回归方法(既克服了传统方法的不足,又有效地消除了因素变量之间的多重共线性),分析了影响我国外商直接投资的因素,以及其影响程度,为我国进一步引进外商直接投资提供了有益的定量依据。  相似文献   
52.
The implementation of quality management in social organizations. An evaluation of the results The article presents the results of an evaluation of the introduction prozess of the quality management in social organizations. In particular it illustrates the grounds of the specific features and differences of the participation procedures in this process. A prerequisite for a success is the bottom up procedere that recognizes and uses the resources, competencies and functions of the employees and managers. A formal optimizing of the operational processes will not induce a reorientation. If it does not succeed to internalize new approaches on the basis of a longterm learning process, the quality management will remain a paper and it will fail.  相似文献   
53.
In recent years, there has been a growing interest in modelling integred-valued time series. In this article, we propose a modified and generalized version of the first order rounded integer-valued autoregressive RINAR(1) model, originally introduced by Kachour and Yao (2009 Kachour , M. , Yao , J. F. ( 2009 ). First-order rounded integer-valued autoregressive (RINAR(1)) process . Journal of Time Series Analysis 30 ( 4 ): 417448 .[Crossref], [Web of Science ®] [Google Scholar]). Indeed, this class can be considered as an alternative of classical models based on the thinning operators. Using a Markov chain method, conditions for stationarity and the existence of moments are investigated. Least squares estimator of the model parameters is considered and its consistence is established. Finally, we describe the price change data using a model of the new class.  相似文献   
54.
This article considers the problem of parameter estimation for two dimensional (2-D) multi-component harmonics in non zero-mean multiplicative and additive noise. The least squares estimators (LSEs) are proposed to estimate the coherent model parameters, and some statistical results of the LSEs are obtained, including strong consistency, strong convergence rate, and asymptotic normality. Furthermore, the LSEs-based estimators are proposed to estimate the noncoherent model parameters, and the strong consistency and the asymptotic normality are also proved. Finally, some numerical experiments are performed to see how the asymptotic results work for finite sample sizes.  相似文献   
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56.
Tremendous increases in indirect costs can be found in many industries. Consequently, life cycle cost analysis models are getting more important in strategic cost management. However, existing models differ significantly from each other as they have been developed mainly for specific applications. In order to enable a common use of those models, a standardization of these models is required. We examine the potentials of standardizing models for life cycle cost analysis. In a first step, requirements regarding a standard model are derived from literature. As a second step, existing approaches found in literature are compared to the afore derived demands and it is analyzed to what extent they match the standardization requirements. Based on this comparison, we identify and discuss avenues for further research.  相似文献   
57.
The results of this paper are the continuation of the research presented by Bieniek [Optimal bounds for the mean of the total time on test for distributions with decreasing generalized failure rate. Statistics. 2016;50:1206–1220]. We consider the remaining total time on test after a given failure in a life test experiment. We derive sharp upper bounds on the mean of the total time on test optimal in the class of distributions with increasing generalized failure rate with respect to generalized Pareto distributions. Specific results are obtained for distributions with increasing density and increasing failure rate. We also provide exemplary numerical values of the obtained bounds and we compare them with the corresponding bounds for distributions with decreasing generalized failure rate.  相似文献   
58.
《统计学通讯:理论与方法》2012,41(16-17):2959-2982
In this article, we propose a new approach to sieve estimation for a general regression function when the dimension of the finite dimensional subspaces is a random quantity depending on the values of the observations.

The technique is introduced with the help of a simulation study on a functional linear model under extremely mild assumptions.

A sketch of the proof concerning the main statements is then given in the more general case when the regression function is not necessarily linear.  相似文献   
59.
We derive the optimal regression function (i.e., the best approximation in the L2 sense) when the vector of covariates has a random dimension. Furthermore, we consider applications of these results to problems in statistical regression and classification with missing covariates. It will be seen, perhaps surprisingly, that the correct regression function for the case with missing covariates can sometimes perform better than the usual regression function corresponding to the case with no missing covariates. This is because even if some of the covariates are missing, an indicator random variable δδ, which is always observable, and is equal to 1 if there are no missing values (and 0 otherwise), may have far more information and predictive power about the response variable Y than the missing covariates do. We also propose kernel-based procedures for estimating the correct regression function nonparametrically. As an alternative estimation procedure, we also consider the least-squares method.  相似文献   
60.
中国的实际生育水平一直存在争议,2010年的普查数据为我们提供了考察生育水平的新证据。本文根据2000年人口普查资料,使用人口模拟模型,选取不同的生育水平方案,来模拟2001—2010年历年的出生人口数量和2010年的人口总量,以判断2000—2010年生育水平。结果表明,现行的总和生育率在1.7以下,1.6左右,2010年在1.6以下,但降到1.5以下的可能性也非常大。为了避免低生育的更进一步的严重后果,中国应该适时地完善生育政策。  相似文献   
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