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1.
本文研究协变量缺失下变系数部分非线性模型的统计推断.利用逆概率加权最小二乘方法给出了参数分量和非参数分量的估计,并证明了它们的渐近正态性.  相似文献   

2.
主要研究半参数单调变系数部分线性EV模型的估计问题,提出了单调纠偏profile最小二乘估计方法,给出了模型中未知参数和单调变系数函数的估计,并在适当条件下证明了参数估计的渐近正态性和非参数单调估计的渐近性质.最后利用计算机数值模拟验证了本文所提方法的可行性及有限样本估计结果的性质.  相似文献   

3.
非参数可靠性模型中一些参数的区间估计   总被引:1,自引:1,他引:0  
研究了非参数模型下的一些可靠性参数的推断. 基于U-统计量的渐近性质和变换方法,导出了这些参数的具有渐近正确覆盖率的置信区间. 给出了比较这些置信区间效果的模拟结果.  相似文献   

4.
考虑了半函数部分线性回归模型的估计问题.在函数型数据下发展了经验似然方法.构造了参数分量的经验似然比函数,得到提出的经验对数似然比渐近于χ~2分布,可用此结果构造兴趣参数的置信域.同时,也给出了非参数函数的估计,在一定的正则条件下给出了其收敛速度.  相似文献   

5.
考虑具有Laplace边际分布的二元一阶自回归时间序列模型, 给出该模型的性质及参数的条件最小二乘估计, 并讨论估计量的相合性和渐近正态性. 最后给出数值模拟和实例分析.  相似文献   

6.
检验了部分线性回归模型中的函数部分是否为常数, 在备择假设下, 先用局部多项式方法估计出函数部分, 在估计中忽略了参数部分, 将其并入误差项, 再使用二阶段估计法, 直接应用最小二乘方法, 估计出参数部分, 并讨论了它们的渐近性质. 计算了零假设下广义似然比检验统计量的表达式, 并给出其渐近分布.  相似文献   

7.
利用原始自助法(wild bootstrap)估计异方差线性模型,建立了异方差线性模型中参数部分的最小二乘估计的渐近分布,给出了非齐次方差的协差阵的一个相合估计.  相似文献   

8.
研究了部分线性可加模型在参数部分附加有随机约束条件且存在多重共线性时的估计问题.文中基于Profile最小二乘方法、混合回归估计和Liu估计方法,提出了参数分量的Profile混合Liu估计,给出了估计量的偏和方差,并讨论了其渐近分布.  相似文献   

9.
针对解释变量带有测量误差的部分函数型线性回归模型,引入一个合适辅助向量,构造出未知参数的经验对数似然比函数,给出了未知参数和未知系数的极大经验似然估计。进一步证明了所构造似然比函数具有渐近卡方分布,并基于此构造了未知参数的渐近置信域。同时,也证明了给出的未知参数的估计与最小二乘估计一样具有渐近正态性。最后给出系数函数的收敛速度,达到了最优收敛速度。讨论的结果说明经验似然方法对部分函数型EV回归模型的统计推断是有效的。  相似文献   

10.
针对非参数混合效应模型提出估计方法,通过B样条的方法估计非参数函数,使用惩罚(非加权)最小二乘方法估计随机效应,然后通过构造正态似然函数得到方差的估计,并且证明了方差分量的相合性和函数部分的渐近正态性;最后给出数字模拟来展示所提出方法的估计效果,结果表明:该方法给出的估计效果良好,且在数值上是稳定的。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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