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1.
Liu等人在聚类抽样的情形下基于贝塔二项分布模型讨论了风险比的区间估计问题.本文以他们的研究为背景,建立了一类聚类抽样样本的广义线性模型,并采用拟似然方法导出相应的广义估计方程,从而获得风险比的直接估计.这种方法不需要假定分布的具体形式,因而比Liu等人的方法具有更好的适用性.最后在一定正则条件下证明了估计的相合性和渐近正态性质.  相似文献   

2.
本文讨论条件矩限制回归模型的参数估计.使用非参数估计方法给出条件密度和条件均值的估计,在此基础上给出参数的广义矩估计.进一步讨论了估计的渐近正态性.  相似文献   

3.
本文基于多类型复发事件数据,讨论了一个新的加性乘积比率回归模型,该模型包括两部分,其中第一部分为可加Aalen模型,其中协变量影响为加性的且与时间有关.第二部分为Cox回归模型,其中协变量有乘性影响.利用估计方程的方法,给出了该模型中未知参数和非参数函数的一种估计方法,并利用现代经验过程理沦证明了所得估计的相合性和渐近正态性.  相似文献   

4.
本文研究一类带扩散的聚合物模型,并在参数γ>0和γ<0两种不同情形给出定性分析.主要运用抛物型方程比较原理和相应常微分方程的结论得到反应扩散方程的先验估计和渐近性分析.  相似文献   

5.
经验似然方法已经被广泛用于许多模型的统计推断.基于经验似然对Logistic回归模型进行统计诊断.首先给出模型的估计方程,进而得到模型参数的极大经验似然估计;其次,基于经验似然研究了三种不同的影响曲率;最后通过实例分析,说明了统计诊断方法的有效性.  相似文献   

6.
本文在成组复发事件下研究了一个一般半参数的加性乘积比率模型,利用估计方程的理论,给出了该模型中未知参数和基本比率函数的估计,同时利用现代经验过程理论证明了所得估计的相合性和渐近正态性.  相似文献   

7.
Pinching-估计是研究解的凸性的一种重要方法,主要给出了半线性二阶椭圆偏微分方程的Pinching-估计,并将其推广到一类完全非线性二阶椭圆偏微分方程.  相似文献   

8.
经验似然方法己经被广泛应用于许多模型的统计推断.本文基于经验似然对部分线性模型进行统计诊断.首先给出模型的估计方程,进而得到模型参数的极大经验似然估计;其次,基于经验似然研究了三种不同的影响曲率;最后通过随机模拟和实例分析,说明了统计诊断方法的有效性.  相似文献   

9.
本文基于Bnyesian估计理论,讨论了MA模型阶的识别,在关于阶和参数的一个一般先验分布下,给出了阶的估计的Bayesian准则,并证明了该估计方法具有强相合性.  相似文献   

10.
复发事件下一般半参数比率回归模型   总被引:1,自引:1,他引:0  
收稿在复发事件数据下,研究了-个一般半参数比率回归模型中参数的估计问题,给出了该模型中未知参数和非参数函数的一种估计方法,并证明了这些估计的相合性和渐近正态性.  相似文献   

11.
The method of generalized estimating equations (GEE) introduced by K. Y. Liang and S. L. Zeger has been widely used to analyze longitudinal data. Recently, this method has been criticized for a failure to protect against misspecification of working correlation models, which in some cases leads to loss of efficiency or infeasibility of solutions. In this paper, we present a new method named as 'weighted estimating equations (WEE)' for estimating the correlation parameters. The new estimates of correlation parameters are obtained as the solutions of these weighted estimating equations. For some commonly assumed correlation structures, we show that there exists a unique feasible solution to these weighted estimating equations regardless the correlation structure is correctly specified or not. The new feasible estimates of correlation parameters are consistent when the working correlation structure is correctly specified. Simulation results suggest that the new method works well in finite samples.  相似文献   

12.
对图像与信号处理中遇到的一类齐次多项式优化问题,本文首先借助平移技术将目标函数转化为凸函数,然后结合初始点技术提出了求解该类问题的一个全局优化算法.与求解该类问题的幂方法相比,本文给出的方法不但能在一般情形下保证算法的全局收敛性,而且数值结果表明在多数情况下可以得到问题的一个全局最优值解.  相似文献   

13.
李世航  肖箭 《大学数学》2005,21(2):98-101
主要讨论一类差分不等式,研究了它们的估计和计算,给出估计公式和算法,推广了文[1]的结果.  相似文献   

14.
In the study of complex organisms, clarifying the association between the evolution of coding genes and the measures of functional variables is of fundamental importance. However, traditional analysis of the evolutionary rate is either built on the assumption of independence between responses or fails to handle a mixture distribution problem. In this paper, we utilize the concept of generalized estimating equations to propose an estimating equation to accommodate continuous and binary probability distributions. The proposed estimate can be shown to have consistency and asymptotic normality. Simulations and data analysis are also presented to illustrate the proposed method.  相似文献   

15.
在响应变量带有单调缺失的情形下考虑高维纵向线性回归模型的变量选择.主要基于逆概率加权广义估计方程提出了一种自动的变量选择方法,该方法不使用现有的惩罚函数,不涉及惩罚函数非凸最优化的问题,并且可以自动地剔除零回归系数,同时得到非零回归系数的估计.在一定正则条件下,证明了该变量选择方法具有Oracle性质.最后,通过模拟研究验证了所提出方法的有限样本性质.  相似文献   

16.
何穗  王芬 《应用数学学报》2012,35(4):728-736
本文在成组复发事件下研究了一个一般半参数的边际变换模型,利用估计方程的理论,给出了该模型中未知参数和基本比率函数的估计,同时利用现代经验过程理论证明了所得估计的相合性和渐近正态性.  相似文献   

17.
In this article, we propose an unbiased estimating equation approach for a two-component mixture model with correlated response data. We adapt the mixture-of-experts model and a generalized linear model for component distribution and mixing proportion, respectively. The new approach only requires marginal distributions of both component densities and latent variables. We use serial correlations from subjects’ subgroup memberships, which improves estimation efficiency and classification accuracy, and show that estimation consistency does not depend on the choice of the working correlation matrix. The proposed estimating equation is solved by an expectation-estimating-equation (EEE) algorithm. In the E-step of the EEE algorithm, we propose a joint imputation based on the conditional linear property for the multivariate Bernoulli distribution. In addition, we establish asymptotic properties for the proposed estimators and the convergence property using the EEE algorithm. Our method is compared to an existing competitive mixture model approach in both simulation studies and an election data application. Supplementary materials for this article are available online.  相似文献   

18.
??The multivariate response is commonly seen in longitudinal and cross-sectional design. The marginal model is an important tool in discovering the average influence of the covariates on the response. A main feature of the marginal model is that even without specifying the inter-correlation among different components of the response, we still get consistent estimation of the regression parameters. This paper discusses the GMM estimation of marginal model when the covariates are missing at random. Using the inverse probability weighting and different basic working correlation matrices, we obtain a series of estimating equations. We estimate the parameters of interest by minimizing the corresponding quadratic inference function. Asymptotic normality of the proposed estimator is established. Simulation studies are conducted to investigate the finite sample performance of the new estimator. We also apply our proposal to a real data of mathematical achievement from middle school students.  相似文献   

19.
Case-cohort design usually requires the disease rate to be low in large cohort study,although it has been extensively used in practice.However,the disease with high rate is frequently observed in many clinical studies.Under such circumstances,it is desirable to consider a generalized case-cohort design,where only a fraction of cases are sampled.In this article,we propose the inference procedure for the additive hazards regression under the generalized case-cohort sampling.Asymptotic properties of the proposed estimators for the regression coefcients are established.To demonstrate the efectiveness of the generalized case-cohort sampling,we compare it with simple random sampling in terms of asymptotic relative efciency.Furthermore,we derive the optimal allocation of the subsamples for the proposed design.The fnite sample performance of the proposed method is evaluated through simulation studies.  相似文献   

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