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1.
赵景等 《统计研究》2019,36(8):100-113
本文基于四要素双层嵌套的生产函数,利用1990-2016年全国层面及省际层面数据测算投资效率,并分析其空间结构特征及演变轨迹,检验投资效率匹配效应影响因素。研究发现:①1990-2016年我国整体投资效率呈下降趋势,资本-技能劳动匹配效应与整体投资效率走势趋同,快速累积的资本存量和不断升级的资本质量与短缺的技能劳动之间矛盾突出。②东中西部地区投资效率增长非一致性明显。东部地区资本相对投资效率明显高于中西部,但下降幅度大于中西部,中西部与东部地区之间差距缩小,其中匹配效应是区域间投资效率非平衡的主要成因。③若产业结构升级的技能劳动需求不能满足,将引发要素错配,不利于有效投资。房价与工资提升分别通过影响技能劳动供给和需求抑制要素匹配效率;教育和公路设施会对地区要素匹配产生积极影响,改善地区间投资效率非均衡性;地区投资效率存在显著正向空间相关性,毗邻地区的要素流动和经济发展相近地区的技术溢出均对投资效率产生积极的影响。  相似文献   
2.
On Optimality of Bayesian Wavelet Estimators   总被引:2,自引:0,他引:2  
Abstract.  We investigate the asymptotic optimality of several Bayesian wavelet estimators, namely, posterior mean, posterior median and Bayes Factor, where the prior imposed on wavelet coefficients is a mixture of a mass function at zero and a Gaussian density. We show that in terms of the mean squared error, for the properly chosen hyperparameters of the prior, all the three resulting Bayesian wavelet estimators achieve optimal minimax rates within any prescribed Besov space     for p  ≥ 2. For 1 ≤  p  < 2, the Bayes Factor is still optimal for (2 s +2)/(2 s +1) ≤  p  < 2 and always outperforms the posterior mean and the posterior median that can achieve only the best possible rates for linear estimators in this case.  相似文献   
3.
以展览业发达的东莞为研究样地,利用因素分析与聚类研究相结合的综合定量方法,对专业观众的观展动机进行综合评估及分类研究。研究表明,专业观众的非购买动机甚过购买动机,他们观展动机的四个维度因子依次为:搜集信息、建立市场关系、考察奖励、采购行为。本研究还发现专业观众的观展动机分为目标模糊型、信息搜集导向型、目标多维明确型三种类型。  相似文献   
4.
Summary.  Factor analysis is a powerful tool to identify the common characteristics among a set of variables that are measured on a continuous scale. In the context of factor analysis for non-continuous-type data, most applications are restricted to item response data only. We extend the factor model to accommodate ranked data. The Monte Carlo expectation–maximization algorithm is used for parameter estimation at which the E-step is implemented via the Gibbs sampler. An analysis based on both complete and incomplete ranked data (e.g. rank the top q out of k items) is considered. Estimation of the factor scores is also discussed. The method proposed is applied to analyse a set of incomplete ranked data that were obtained from a survey that was carried out in GuangZhou, a major city in mainland China, to investigate the factors affecting people's attitude towards choosing jobs.  相似文献   
5.
To explore the projection efficiency of a design, Tsai, et al [2000. Projective three-level main effects designs robust to model uncertainty. Biometrika 87, 467–475] introduced the Q criterion to compare three-level main-effects designs for quantitative factors that allow the consideration of interactions in addition to main effects. In this paper, we extend their method and focus on the case in which experimenters have some prior knowledge, in advance of running the experiment, about the probabilities of effects being non-negligible. A criterion which incorporates experimenters’ prior beliefs about the importance of each effect is introduced to compare orthogonal, or nearly orthogonal, main effects designs with robustness to interactions as a secondary consideration. We show that this criterion, exploiting prior information about model uncertainty, can lead to more appropriate designs reflecting experimenters’ prior beliefs.  相似文献   
6.
中国企业渠道联盟关系影响因素研究   总被引:1,自引:0,他引:1  
渠道联盟被认为是渠道关系中最高、最好的形式。学术界对渠道联盟关系影响因素的研究主要集中在承诺、信任、沟通与合作等方面。本文实证研究了影响中国企业渠道联盟关系的若干因素及其影响程度,特别是探讨了私人关系和行政因素等的影响程度。  相似文献   
7.
管理技能的因子分析及其对绩效影响的实证研究   总被引:9,自引:1,他引:9  
本文以在沪三资企业中12家电子制造企业管理人员的有效问卷271份为第一手资料,用因子分析等方法分析了构成这些人员管理技能的四大要素为:领导与激励技能、计划组织与协调技能、决策与创新技能、控制与授权技能;研究的结果表明,并非每项管理技能对提升企业的绩效都起同样的作用。不同绩效企业的管理者对各种管理技能的运用程度是有所不同的。  相似文献   
8.
Substantial evidence supports the value of outdoor education programs for promoting healthy adolescent development, yet measurement of program outcomes often lacks rigor. Accurately assessing the impacts of programs that seek to promote positive youth development is critical for determining whether youth are benefitting as intended, identifying best practices and areas for improvement, and informing decisions about which programs to invest in.We generated brief, customized instruments for measuring three outcomes among youth participants in Baltimore City Outward Bound programs: conflict management, emotional self-efficacy, and problem solving confidence. Measures were validated through exploratory and confirmatory factor analyses of pilot-testing data from two groups of program participants. We describe our process of identifying outcomes for measurement, developing and adapting measurement instruments, and validating these instruments.The finalized measures support evaluations of outdoor education programs serving urban adolescent youth. Such evaluations enhance accountability by determining if youth are benefiting from programs as intended, and strengthen the case for investment in programs with demonstrated success.  相似文献   
9.
The use of large-dimensional factor models in forecasting has received much attention in the literature with the consensus being that improvements on forecasts can be achieved when comparing with standard models. However, recent contributions in the literature have demonstrated that care needs to be taken when choosing which variables to include in the model. A number of different approaches to determining these variables have been put forward. These are, however, often based on ad hoc procedures or abandon the underlying theoretical factor model. In this article, we will take a different approach to the problem by using the least absolute shrinkage and selection operator (LASSO) as a variable selection method to choose between the possible variables and thus obtain sparse loadings from which factors or diffusion indexes can be formed. This allows us to build a more parsimonious factor model that is better suited for forecasting compared to the traditional principal components (PC) approach. We provide an asymptotic analysis of the estimator and illustrate its merits empirically in a forecasting experiment based on U.S. macroeconomic data. Overall we find that compared to PC we obtain improvements in forecasting accuracy and thus find it to be an important alternative to PC. Supplementary materials for this article are available online.  相似文献   
10.
曾玉林 《云梦学刊》2012,33(1):67-71
耕地承包农户的户主年龄、家庭非农收入、土地转让行为选择、农户择业意愿、耕地条件与环境等因素与耕地利用率之间存在显著相关。对此,政府首先必须加强对农民的重农教育,增强农民珍爱耕地的自觉性;其次,应创新耕地管理制度,引导土地合理流转;其三,推进农村土地流转规范,提升耕地资产价值效能;其四,加大支农惠农政策力度,提高农业比较收益;其五,扩大对农村投入,改善农村农业基础设施建设。  相似文献   
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