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2002年电力体制改革以后,我国电力行业取得了迅猛发展,电力需求量与生产量增长迅速,社会用电量也一路飙升.为了明确各影响因素与用电量的影响关系,以我国2002-2015年用电量相关统计数据为基础,选取国民生产总值、人口总量、第二产业GDP、能源消耗总量、城镇化率、单位GDP电耗、货物进出口总额、房屋施工面等12个指标,通过主成分分析法进行系统化研究.结果显示,我国用电量与第一主成分显著相关,而第二主成分没有显著相关关系.最后,针对具体分析结果,为相关政策制定和现状分析提供了建议. 相似文献
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影响中学生数学成绩因素的通径分析 总被引:6,自引:0,他引:6
用绵阳市 6 0 0名初中学生构成样本 ,采用J¨oreskog提出的线性结构方程式模型理论 ,以及J¨oreskog和S¨orbom开发的软件系统LIREL8.3对调查的资料进行分析。结果表明 :用 2 0个显在变量和 10个隐在变量研究影响中学生数学成绩的因素 ,最后有 13个显在变量入选构成外生模型 ,有 7个隐在变量变量入选构成内生模型。Homeback、Attitud、Views、EQ、IQ和Class这 6个内生的隐在变量对中学生的数学成绩均存在不同程度的影响 ,其中以Attitud、Homeback、IQ和EQ对数学成绩的贡献最大。内生模型中 6个内生的隐在变量的R2 的平均值为 0 .2 0 ,该模型中数学成绩(Mathachi)这一变量中可预测的方差占到了 4 1% (R2 =0 .4 1) ,将这两者结合起来考虑 ,所建立的模型应当是比较有说服力的。 相似文献
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运用2005-2014年我国18个高技术行业中大中型内资企业的面板数据,实证分析了RD经费内部支出、RD人员全时当量、政府资金、技术改造费用支出以及新增固定资产对高技术产业自主创新能力的影响.实证结果显示,从全部行业来看,RD经费内部支出、技术改造经费支出和政府资金对我国高技术产业自主创新能力具有显著的正向影响,新增固定资产和RD人员全时当量对我国高技术产业自主创新能力有一定的正向影响,但不显著.从细分行业来看,这些因素对各行业自主创新能力的影响又有所不同. 相似文献
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本文在对内蒙古自治区进出口贸易的现状进行分析的基础上,选取1988-2007年的数据样本,对影响内蒙古外贸出口的因素进行了实证分析。实证分析的结果表明:进口额(IM)、全社会固定资产总值(IN)和汇率(EXC)对内蒙古地区的外贸出口均有积极促进的作用,其中进口对出口促进作用最大,而外商直接投资(FDI)却被证明是一个阻止出口额增长的因素。根据分析的结果,提出了改善内蒙古出口贸易的对策建议。 相似文献
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在定性分析财险公司偿付能力内外部影响因素的基础上,考虑规模因素,本文从大、中、小规模公司中各选取有代表性的一家,采用灰色关联法对三家公司2007~2011年的数据进行偿付能力影响因素对比分析.实证结果表明,同一因素对不同规模的财险公司偿付能力的影响程度存在较大差异,因而不同规模的公司在管理偿付能力风险时侧重点应有所不同. 相似文献
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《数学的实践与认识》2019,(21)
为探究江苏地区职业女性生育二孩意愿的影响因素,对江苏地区1个副省级市,12个地级市,22个县级市,19个县地区发放1000份问卷进行调查,收回有效问卷921份.对职业女性生育二孩有意愿、无意愿、不确定的情况作单因素方差分析,筛选出影响因素,分析结果表明不同户籍、年龄、学历文化程度、婚育情况、家庭人口数、家庭经济状况、父母态度是职业女性生育二孩意愿的影响因素.再以职业女性生育二孩意愿为因变量,有意愿为对照组,作Logistic多因素回归分析,得到各个影响因素之间对职业女性生育二孩无意愿结果的影响回归方程.分析结果表明家庭人口情况和父母态度对职业女性生育二孩的意愿有着重要的影响. 相似文献
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《数学的实践与认识》2015,(20)
针对湖南省就业人数的影响因素问题,首先利用灰关联分析和相关系数法优选出对就业人数影响较大的指标,然后对优选的指标进行主成分分析得出了主成分表达式,最后将就业人数与主成分进行回归得到了就业人数的拟合方程.结果表明,城市化水平、国内生产总值和居民消费水平对湖南省就业人数的影响最大,从而为政府有关部门的决策提供了一定的参考依据. 相似文献
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不同的影响因素对天然气需求的影响程度存在差异,为充分认识上述差异,利用相对关联度定量刻画天然气需求量与影响因素之间的关联程度。依据重要性优先原则,采用逐步回归法逐次地对影响因素的统计显著性进行检验,深度挖掘有效驱动因素,构建“最佳”逐步回归C-D生产函数模型预测未来天然气需求走势。结果表明:(1)GDP是影响中国天然气需求的最主要因素,能源消费结构也是重要的有效驱动因素之一;(2)基于重要有效驱动因素构建的“最佳”逐步回归C-D生产函数模型实现了历史数据拐点拟合预测,具有良好的预测性能,预测结果可作为确定未来天然气需求的重要参考依据;(3)预测2020~2030年中国天然气需求量呈稳步增长趋势,但增速有所减缓,到2030年天然气需求量达约5660亿立方米,天然气需求量增长率降至4%。 相似文献
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Efthymios G. Tsionas 《商业与工业应用随机模型》1999,15(3):147-168
Very often, one needs to perform (classical or Bayesian) inference, when essentially nothing is known about the distribution of the dependent variable given certain covariates. The paper proposes to approximate the unknown distribution by its non-parametric counterpart—a step function—and treat the points of the support and the corresponding density values, as parameters, whose posterior distributions should be determined based on the available data. The paper proposes distributions should be determined based on the available data. The paper proposes Markov chain Monte Carlo methods to perform posterior analysis, and applies the new method to an analysis of stock returns. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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我国上市公司资本结构影响因素实证分析 总被引:17,自引:0,他引:17
本文选取了可能影响企业资本结构的多个指标变量进行分析 ,利用主成分分析提供的方法将变量综合成彼此互不相关的少数几个主成分。再用主成分 (作为回归自变量 )对企业的 5种资本负债比 (作为回归因变量 )进行多元回归分析 ,得出了影响企业资本结构的主要因素 ,以及这些因素与企业资本结构之间的关系 ,为企业确定资本结构提供参考依据 ,为企业财务决策提供支持。 相似文献
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Ruin capital is a function of premium rate set to render the probability of ruin within finite time equal to a given value. The analytical studies of this function in the classical Lundberg model of risk with exponential claim sizes done in Malinovskii (2014) have shown that the ruin capital’s shape is surprisingly simple. This work presents the results of related simulation studies. They are focused on the question whether this shape remains similar in Sparre Andersen’s model of risk. 相似文献
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本文在问卷调查的基础上对影响老年人幸福的因素进行了相关分析 ,并通过逐步回归和因子分析方法给出了影响老年人幸福的主要因素。 相似文献
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随着我国城镇化的快速发展,大批农业劳动力向城市转移,农业总产值及其主要影响因素的研究已经成为热点问题.为研究我国农业总产值的主要影响因素,本文借助多元回归分析的相关理论抽取了2016年我国农业投入的31个省市的相关截面数据,采用最小二乘法,利用SPSS软件进行多元回归分析,得到回归模型,并基于该模型找出我国农业总产值的主要影响因素. 相似文献
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This study analyses the existence, stability and self-organizationof formation flight utilized by migrant birds. Air is approximatedas an incompressible inviscid flow, while birds are modelledas elliptically loaded lifting-lines. Application of conventionalwing theory leads to newly derived, basic equations that describethe problem as a dynamical system of multiple wings interactingwith each other through induced flow field. Formation flightis defined as the steady-state solution of the basic equations,in particular the solution that all the birds fly at the samespeed. In the case of a prescribed thrust, constant transverseinterval between adjacent birds, and a flock of physically identicalbirds, analytical study of the basic equations reveals the factsthat (1) formation flight is self-organized and (2) this formationflight is stable. The new implication is that a configurationof formation emerges as a result of nonlinear dynamical interactionbetween many birds and that this nonlinear dynamical systemdoes not exhibit chaotic behaviour. Numerical calculation hasalso been done for cormorant-type birds with the same transverseinterval between flock members. The proposed numerical schemequickly converges to very accurate results owing to the recentlyderived, closed-form expression of induced velocity distributionaround an elliptically loaded lifting-line. Transverse intervalsbetween birds are found to be a more important factor than thenumber of birds. Configurations of formations are found to beinverted U rather than inverted V. In these formations everybird enjoys the same amount of drag reduction. 相似文献
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Principal component analysis is integrated with canonical analysis to examine aspects of the competitiveness of two different sectors of the Greek manufacturing, i.e. the food and the beverage industries. Different measures of labour productivity, vertical integration, technological innovation and size of the firms which are considered as critical factors of industrial competitiveness are used in the application of the principal component analysis. Canonical analysis is then applied to correlate the variables of labour productivity with the other variables. In the case of the food and beverage integrated sector, the results of the principal component analysis pinpoint that there are two main principal components: (a) labour productivity and vertical integration, and (b) technological innovation and size. The first factor depicts the internal organizational, structural and production processes changes realized so that the competitiveness of the sector firms improves, whereas the second factor reflects the response of the sector to technological and growth trends. The two variables of labour productivity are affected by the degree of vertical integration and, at a lesser degree, by a common factor of the size of the firm and the level of investment for technological innovation. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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中国出口贸易与经济增长关系的实证研究 总被引:1,自引:0,他引:1
王平 《数学的实践与认识》2011,41(15)
围绕出口贸易与中国经济增长之间的关系,首先采用计量经济学分析方法,运用Eviews软件对出口贸易和经济增长的关系进行实证分析,在此基础上针对我国出口贸易发展中存在的问题提出相应的对策建议,进而对于我国经济免受全球金融危机危害具有一定的现实意义. 相似文献
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Ramy Elitzur 《European Journal of Operational Research》2011,215(3):705-712
We study a model of entrepreneurs who compete in an auction-like setting for venture capital (VC) funding in a setting where limited capital dictates that the VC can only finance the best entrepreneurs. With asymmetric information, VCs can only assess entrepreneurs by the progress of development, which, in equilibrium, reveals the quality of the new technology. Using an asymptotic analysis, we prove that in attractive industries having a large number of entrepreneurs competing for VC funding could lead to underinvestment in technology by entrepreneurs as the effort exerted by losing entrepreneurs is wasted. The study then proceeds to characterize the conditions under which a greater number of competing entrepreneurs is better. The model also demonstrates that VCs could possibly increase their payoff by concentrating on a single industry. In addition, the study also provides some insights on the effects of multiple investments by VCs and the effects of competition among VCs on the same investments. 相似文献
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Alireza Amirteimoori Sohrab Kordrostami Maryam Sarparast 《Applied mathematics and computation》2006,180(2):444-452
Data envelopment analysis is a mathematical programming technique for identifying efficient frontiers for peer decision making units with multiple inputs and multiple outputs. These performance factors (inputs and outputs) are classified into two groups: desirable and undesirable. Obviously, undesirable factors in production process should be reduced to improve the performance. In the current paper, we present a data envelopment analysis (DEA) model in which can be used to improve the relative performance via increasing undesirable inputs and decreasing undesirable outputs. 相似文献