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基于1997-2016年中国30个省级地区的数据,建立面板分位数回归模型考量对外贸易与经济增长对不同分位水平二氧化碳排放的影响.研究发现:在各分位点对外贸易对碳排放的影响为负,但仅在高分位点显著,并且对外贸易的减排效应表现出随碳排放量增加而增加的趋势.经济增长在50%分位点以外的其他分位点对碳排放具有显著的促进作用,但环境库兹涅茨假说只在低排放省份和高排放省份有效;进一步研究显示,对外贸易通过促进经济增长对碳排放产生的正向间接影响大于负向直接影响,对外贸易总体上加剧了环境污染,验证了"污染天堂假说". 相似文献
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在介绍分位数回归方法的基础上,讨论了分位数回归模型在研究影响大学生成绩变化因素方面的应用,与最小二乘回归模型对比,分位数回归能有效地描述数据尾端的分布情况. 相似文献
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首先在考虑到人力资本质量的基础上,利用1993-2008的我国30个地区面板数据基于Mamquist指数法测度了我国地区TFP值,然后运用分位数回归技术研究了异质性人力资本对TFP增长不同阶段的作用机制,回归结果表明非熟练劳动只在TFP增长的初级阶段产生正向显著的促进作用,当TFP增长到一定水平(80%分位数以上)抑制了TFP增长.熟练劳动资本从TFP增长的20%分位数处对发达地区产生显著正向拉动作用,而且这种作用一致增强,地区间技术差异从30%分位数处开始一致地对TFP增长产生显著正向推动用. 相似文献
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利用分位数回归模型探讨了原油价格、道琼斯指数、美元汇率、上证指数和利率对国内黄金价格的影响.实证分析结果表明在不同分位数水平上各因素对黄金价格的影响不一样.分位数回归能够从历史数据中挖掘出更多的信息,更有利于投资者了解影响黄金价格波动的因素从而做出更好的决策. 相似文献
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本文应用最优化理论,对固定效应的面板数据分位数回归模型,提出一种模式搜索方法,此方法可以同时估计出所有分位点处的解释变量系数和所有个体的固定效应值。进一步利用蒙特卡洛模拟比较现有文献中涉及的面板数据分位数回归方法,结果显示无论误差项是否满足经典假设,模式搜索分位数回归法较之其他分位数回归估计方法更为有效. 相似文献
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《Applied Mathematics Letters》2007,20(7):770-772
In this work, we point out that the proof of Theorem 2 in [E. Pap, Extension of null-additive set functions on algebra of subsets, Novi Sad J. Math. 31 (2) (2001) 9–13] is incorrect and give a correct proof. Moreover, we also get a corresponding theorem on extension of the weakly null-additive set function. 相似文献
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运用灰色系统方法,对原丝性能与碳纤维强度之间的关系进行了灰色关联分析。结果表明,原丝弹性与原丝强度对碳纤维强度影响较大,而原丝纤度与原丝伸度对碳纤维强度影响较小。 相似文献
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N. A. Shirokov 《Journal of Mathematical Sciences》2006,134(4):2320-2323
Let Λα be the analytic Holder class in the unit disk
. For f ∈ Λα and
, let Mf (I) = max
I |f|. Assume that I and J are arcs such that |J| = 2|I| and J and I have the same midpoint. Then
It is proved that this estimate cannot be improved. Bibliography: 1 title.
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Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 315, 2004, pp. 149–154. 相似文献
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研究“右行左超车”规则在高速公路不同交通负荷下对通行能力及安全性的影响。引入超车欲望值及状态改变率的概念,基于交通流元胞自动机模型,建立了“右行左超车”规则下的单向双车道和三车道换道规则及相应的超车规则。选取5个评价参数,针对两车道模型,将“右行左超车”规则与无规则下的换道超车对交通效率与安全表现的影响进行对照试验。试验结果表明:在安全表现方面,低负荷状态下“右行左超车”规则较无规则情形要差,而在高负荷状态下,该规则较无规则情形好;在通行能力方面二者差别不大;试验结果还表明:无论是有规则还是无规则,提高车道的最大与最小限速不仅可以提升道路的通行能力,而且可以提升安全性。最后分析了模型的优缺点,并指出了改进的方向。 相似文献
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E. Vasserot 《Compositio Mathematica》2002,131(1):51-60
It was proved by Ginzburg, Mirkovic and Vilonen that the G(O)-equivariant perverse sheaves on the affine Grassmannian of a connected reductive group G form a tensor category equivalent to the tensor category of finite dimensional representations of the dual group G
. In this paper we construct explicitly the action of G
on the global cohomology of a perverse sheaf. 相似文献
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In this paper we show a new inequality that generalizes to the unit sphere the Lebedev-Milin inequality of the exponentiation of functions on the unit circle. It may also be regarded as the counterpart on the sphere of the second inequality in the Szegö limit theorem on the Toeplitz determinants on the circle. On the other hand, this inequality is also a variant of several classical inequalities of Moser-Trudinger type on the sphere. The inequality incorporates the deviation of the center of mass from the origin into the optimal inequality of Aubin for functions with mass centered at the origin, and improves Onofri's inequality with the contribution of the shifting of the mass center explicitly expressed. © 2021 Wiley Periodicals LLC. 相似文献
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N. C. Steele K.‐J. Backstrom 《International Journal of Mathematical Education in Science & Technology》2013,44(5):693-695
In the past decade there have been significant developments in computer technology and solution techniques for analysing business and industrial decision problems. In recent years good modelling systems have become available to ease the burden of model communication. Currently the single most important barrier to increased use of structured approaches to decision modelling is the acquisition of the necessary skills to initially develop models of complex decision systems. This paper examines the modelling process with reference to linear programming. Two related production planning problems are presented and their associated models developed. The relationship between the two problems is such that student modellers are forced to become involved in the important details of the problems and, by examining the nature of solution spaces in constrained optimisation, students are able to rapidly gain confidence and skills in modelling. 相似文献
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