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1.
本文对降秩多元线性模型的参数阵提出了一类有偏线性估计,讨论了许多重要的性质,从而把降秩模型中参数阵的估计问题转化为满秩模型中参数阵的估计问题,为了讨论方便,我们给出了一种特殊情况;最后,讨论了多元线性模型参数阵的Bayes线性估计。  相似文献   

2.
本文研究强地震过程的模型拟合问题,把估计转化为对给定泛函的优化;在不知道随机序列的概率密度函数的情况下估计出模型阶次及未知参数,使实际问题的解决成为可能;在高斯假定下得到非平稳时间序列的协方差矩阵的转移形式.对一个实际的地震过程进行的数字研究结果证明本文方法是有效的.  相似文献   

3.
讨论了椭球约束下协方差阵扰动模型和数据删除模型对线性回归参数的影响问题,给出了在椭球约束下G-M模型与椭球约束下一般线性模型及在椭球约束下数据删除模型中回归参数的估计之间的关系.  相似文献   

4.
定义了广义线性模型中参数的最小二乘估计(LSE)与最佳线性无偏估计(BLUE)的一种新的相对效率,这种相对效率定义为参数估计量的协方差阵的最大相对特征根之比.给出了当设计矩阵满秩,协方差阵非负定时这种新的相对效率的下界,研究了新的相对效率与广义相关系数之间的关系.由本文的讨论可见,当广义线性模型与主成分分析、典型相关分析方法结合应用时,这种相对效率具有很强的实用价值.  相似文献   

5.
讨论多元性回归模型的影响分析问题,获得了多元协方差阵扰动模型与原模型参数阵之间的最佳线性无偏估计(BLUE)的一些关系式;给出了度量影响大小的距离测度和它的计算公式.  相似文献   

6.
混合效应的线性模型中含有两类参数:一类是固定效应参数,另一类是随机效应部分的方差分量参数.本文主要研究讨论了对于在线性混合模型中的固定效应参数,将不同的线性混合模型转化为满足Guass-Markov假设的线性模型,在此基础上,根据不同的情况,对其中的固定效应参数作最小二乘估计;当模型在较强的复共线性时,相应的对其做岭估计.  相似文献   

7.
将一类随机线性二层规划模型转换为带期望约束的确定性线性二层协方差规划模型,并进一步利用KKT条件将二层协方差规划模型转化为单层规划模型,然后利用分支定界-粒子群混合算法对该模型进行求解.与传统分支定界算法的对比实验表明,该算法有效改善了上层问题的方差结果,且计算效率得到了较显著提高.  相似文献   

8.
在水平井实际应用中,实钻轨道常偏离原设计最优轨道.把实钻轨道与已设计最优轨道的状态变量差值作为参数,建立带有参数的三维水平井最优控制模型,把该模型转化为非线性规划问题求解,讨论了该非线性规划问题的最优解性质.依此性质给出一个全局最优的算法,并将其应用到实际水平井轨道设计中,数值结果表明模型及算法有效、正确。  相似文献   

9.
本文在对ARMAV模型进行预处理的基础上,根据采样向量序列的协方差函数提出了一种向量ARMAV模型的参数线性估计方法:矩阵递推法,包括低阶模型到高阶模型的矩阵递推和同阶模型的矩阵递推。并讨论了模型适用性的检验问题。  相似文献   

10.
参数规划的逆问题   总被引:2,自引:1,他引:1  
提出了参数规划的逆问题,给出了线性参数规划的逆规划,讨论了含有相同参数的一组参数规划的逆问题,并把其转化为求解多目标规划、  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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