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1.
目的 研究核密度的随机加权估计,在一定条件下证明核密度的随机加权估计是有效的.方法 用随机加权法对核密度进行估计.结果 在适当的条件下√nhn(Hn(x)-fn(x))和√nhn(fn(x)-f(x))对几乎所有的样本序列X1,X2,…具有相同的极限分布,即随机加权逼近成立.结论 所提出的随机加权估计优于钱伟民所做的Bootstrap估计,提高了估计的精度.  相似文献   

2.
考虑多元线性模型,用随机加权的办法得到最小距离估计(least distances estimate,LDE)的渐近分布的近似,指出可以用给定样本下随机加权下的LDE的条件分布去近似LDE的渐近分布.  相似文献   

3.
将随机加权法推广到线性测量误差模型,结合分位数回归估计方法,提出线性测量误差模型中参数的随机加权分位数回归方法.在一定条件下,可以用随机加权法得到分位数回归估计量的渐近分布,这种方法避免了估计冗余参数,并且实施方便.通过模拟研究和艾滋病数据验证了随机加权分位数回归方法的有效性.  相似文献   

4.
目的 证明核密度估计随机加权逼近的有效性.方法 用随机加权法对核密度进行估计.结果 在适当的条件下,(√nhn)(Hn(x)-fn(x))和(√nhn)(fn(x)-f(x))对几乎所有的样本序列X1,X2…具有相同的极限分布,同时,得到了随机加权逼近的收敛速度.结论 用随机加权法对核密度进行估计是可行的.  相似文献   

5.
文章在负相协同分布重尾分布条件下,得到了随机变量加权和的尾概率等价关系.通过对负相协同分布随机变量和的最大值、随机个和的最大值的尾概率的渐进性质,以及概率不等式的有关知识,得到的随机变量加权和的尾概率等价关系,消弱了有关文献对独立性的要求;在负相协同分布重尾分布条件下,推广了唐启鹤等人所作的结果,使得到的结论更具有普遍性;由它推导的许多性质,可广泛应用于金融保险及突发事件的研究中.  相似文献   

6.
利用样条函数将分布函数光滑化,得到光滑经验分布函数,在一定的条件下,证明了光没经验分布函数随机加权逼近的相合性。  相似文献   

7.
本文在给出客观判断矩阵的随机干扰因子分布的条件下,证明了当专家数足够多时,加权算术平均综合判断矩阵与加权几何平均综合判断矩阵都依概率收敛到客观判断矩阵,从而解释和验证群体思维具有收敛性.  相似文献   

8.
设{Xi;i∈Nd,d≥2}为独立同分布的随机域,在协方差满足一定条件下,研究独立同分布的随机域最大值的几乎处处中心极限定理,获得权重为加权函数形式的几乎处处中心极限定理.  相似文献   

9.
本文在给出客观判断矩阵的随机干扰因子分布的条件下,证明了当专家数足够多时,加权算术平均综合判断矩阵依概率收敛到客观判断矩阵,从而解释和验证群体思维具有收敛性.  相似文献   

10.
指出对简单的半参数回归模型y=xβ+g(t)+ε,在进行参数估计时,为避免利用BOOtstrap法需进行重新抽样,应用随机加权法构造了涉及参数β的最小二乘随机加权估计量λ,并且在适当的条件下获得了λn分布的Edgcworth展开,其收敛速度可达到O(n^-1/2)。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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