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1.
This article proposes some regularity conditions. On the basis of the proposed regularity conditions, we show the strong consistency of the maximum likelihood estimator (MLE) in exponential family nonlinear models (EFNM) and give its convergence rate. In an important case, we obtain the convergence rate O(n ?1/2(log log n)1/2)—the rate as that in the Law of the Iterated Logarithm (LIL) for iid partial sums and thus cannot be improved anymore.  相似文献   

2.
In this article, we consider a multivariate generalized linear model with adaptive design matrix and general link function. The asymptotic singularity of design matrix of adaptive design presents challenge when establishing the large sample properties of the maximum quasi-likelihood estimate (MQLE). Under some mild conditions, we obtain a strong convergence rate of the MQLE.  相似文献   

3.
This article introduces a novel method, named JC 1, for obtaining G-efficient mixture design to fit quadratic models. The advantage of JC 1 method over existing algorithms is that it gives G-efficient designs without need of generating all the extreme vertices, edge centroids and constraint plane centroids of the mixture experimental region. The performance of the new method is illustrated and its comparison is given with popularly used algorithms—Snee (1975) algorithm and Welch (1985 Welch , W. J. ( 1985 ). ACED: Algorithms for the construction of experimental designs . Amer. Statistician 39 : 146 .[Crossref] [Google Scholar]) ACED algorithm for second-order (quadratic model) designs and it is observed that JC 1 method performs as well as the existing methods or sometimes better than those with additional advantage of large savings in computational efforts.  相似文献   

4.
We consider the estimation of life length of people who were born in the seventeenth or eighteenth century in England. The data consist of a sequence of times of life events that is either ended by a time of death or is right-censored by an unobserved time of migration. We propose a semi parametric model for the data and use a maximum likelihood method to estimate the unknown parameters in this model. We prove the consistency of the maximum likelihood estimators and describe an algorithm to obtain the estimates numerically. We have applied the algorithm to data and the estimates found are presented.  相似文献   

5.
In this paper, we propose an estimation method when sample data are incomplete. We decompose the likelihood according to missing patterns and combine the estimators based on each likelihood weighting by the Fisher information ratio. This approach provides a simple way of estimating parameters, especially for non‐monotone missing data. Numerical examples are presented to illustrate this method.  相似文献   

6.
The self-consistent estimator is commonly used for estimating a survival function with interval-censored data. Recent studies on interval censoring have focused on case 2 interval censoring, which does not involve exact observations, and double censoring, which involves only exact, right-censored or left-censored observations. In this paper, we consider an interval censoring scheme that involves exact, left-censored, right-censored and strictly interval-censored observations. Under this censoring scheme, we prove that the self-consistent estimator is strongly consistent under certain regularity conditions.  相似文献   

7.
This paper shows that, when variables with missing values are linearly related to observed variables, the normal-distribution-based pseudo MLEs are still consistent. The population distribution may be unknown while the missing data process can follow an arbitrary missing at random mechanism. Enough details are provided for the bivariate case so that readers having taken a course in statistics/probability can fully understand the development. Sufficient conditions for the consistency of the MLEs in higher dimensions are also stated, while the details are omitted.  相似文献   

8.
郭鹏辉 《统计研究》2011,28(10):103-110
 本文提出了基于初始值为内生确定下的动态空间固定效应模型,综合考虑了可直接观测和不可直接观测或无法观测的空间效应;推导了模型参数拟极大似然估计量具有的渐近性质及其渐近分布。对参数估计量性质的模拟检验结果表明,似然估计量的渐近性质随着样本容量的增加而改善,且其改善程度对时间维度变化较对空间维度变化更为敏感,在空间单元限定情形下有效增加时间维度可以显著改善估计量性质。中国省域经济收敛性的实证案例分析结果显示,本文构建的综合考虑双重空间结构的空间计量模型具有适用性和合理性。  相似文献   

9.
In a regression model with univariate censored responses, a new estimator of the joint distribution function of the covariates and response is proposed, under the assumption that the response and the censoring variable are independent conditionally to the covariates. This estimator is based on the conditional Kaplan–Meier estimator of Beran (1981 Beran , R. ( 1981 ). Nonparametric regression with randomly censored survival data. Technical Report, University of California, Berkeley, California . [Google Scholar]), and happens to be an extension of the multivariate empirical distribution function used in the uncensored case. We derive asymptotic i.i.d. representations for the integrals with respect to the measure defined by this estimated distribution function. These representations hold even in the case where the covariates are multidimensional under some additional assumption on the censoring. Applications to censored regression and to density estimation are considered.  相似文献   

10.
Doubly truncated data play an important role in the statistical analysis of astronomical observations as well as in survival analysis. In this article, using inverse-probability-weighted (IPW) approaches, we derive the nonparametric maximum likelihood estimator (NPMLE) of joint distribution function with bivariate doubly truncated data. The asymptotic properties of the NPMLE are established. A simulation study is conducted to investigate the performance of the NPMLE.  相似文献   

11.
The Lomax (Pareto II) distribution has found wide application in a variety of fields. We analyze the second-order bias of the maximum likelihood estimators of its parameters for finite sample sizes, and show that this bias is positive. We derive an analytic bias correction which reduces the percentage bias of these estimators by one or two orders of magnitude, while simultaneously reducing relative mean squared error. Our simulations show that this performance is very similar to that of a parametric bootstrap correction based on a linear bias function. Three examples with actual data illustrate the application of our bias correction.  相似文献   

12.
使用科学的方法观测并计算某种社会经济现象的季节性变动,对于把握其真实的环比变动具有重要的现实意义。使用经典方法计算季节指数以反映现象的季节性变动,因其结果不够严谨和完备,是一个至今尚未获得完满解决的问题。为了提高计算季节指数结果的科学性、严谨性、完备性,基于符合三种加法和乘法模型的社会经济现象,解析其中各季节指数之间存在的约束条件,运用数理统计中极大似然估计理论与方法,推导出与经典方法算式相近的季节指数的约束极大似然估计算式,给出季节指数的区间估计,并举例对获得的结果做了计算和对比验证。  相似文献   

13.
In this article, we consider the estimation of distribution function for one modified form of current status data. An inverse-probability-weighted (IPW) estimator and a self-consistent estimator (SCE) are proposed. The asymptotic properties of the IPW estimator are derived. A simulation study is conducted to compare the performances among the IPW estimator, SCE, and the product-limit estimator proposed by Patilea and Rolin (2006 Patilea , V. , Rolin , J.-M. (2006). Product-limit estimators of the survival function for two modified forms of current-status data. Bernoulli 12(5):801819.[Crossref], [Web of Science ®] [Google Scholar]). Simulation results indicate that when right censoring is light and left censoring is heavy, both IPW estimator and SCE can outperform the product-limit estimator. The performances of the IPW estimator and SCE are close to each other.  相似文献   

14.
Abstract. We propose a spline‐based semiparametric maximum likelihood approach to analysing the Cox model with interval‐censored data. With this approach, the baseline cumulative hazard function is approximated by a monotone B‐spline function. We extend the generalized Rosen algorithm to compute the maximum likelihood estimate. We show that the estimator of the regression parameter is asymptotically normal and semiparametrically efficient, although the estimator of the baseline cumulative hazard function converges at a rate slower than root‐n. We also develop an easy‐to‐implement method for consistently estimating the standard error of the estimated regression parameter, which facilitates the proposed inference procedure for the Cox model with interval‐censored data. The proposed method is evaluated by simulation studies regarding its finite sample performance and is illustrated using data from a breast cosmesis study.  相似文献   

15.
By the inequalities established in this article, we obtain the convergence rate of strong law of large numbers for positively associated sequences. The results derived extend and improve the corresponding ones in Vronskii (1999 Vronskii , M. A. ( 1999 ). Rate of convergence in the slln for associated sequences and fields . Theory Probab. Appl. 43 ( 3 ): 449462 .[Crossref], [Web of Science ®] [Google Scholar]).  相似文献   

16.
Let {X j , j ≥ 1} be a strictly stationary negatively or positively associated sequence of real valued random variables with unknown distribution function F(x). On the basis of the random variables {X j , j ≥ 1}, we propose a smooth recursive kernel-type estimate of F(x), and study asymptotic bias, quadratic-mean consistency and asymptotic normality of the recursive kernel-type estimator under suitable conditions.  相似文献   

17.
Assuming that all components of a normal mean vector are simultaneously non negative or non positive, we consider a multivariate two-sided test for testing whether the normal mean vector is equal to zero or not. Since the likelihood ratio test is accompanied with theoretical and computational complications, we discuss two kinds of approximations of the likelihood ratio test. One is based on a conservative critical value determined by a certain inequality. The other is constructed by the approximation of the likelihood ratio test proposed by Tang et al. (1989). We compare the likelihood ratio test and two kinds of approximations through numerical examples regarding critical values and the power of the test.  相似文献   

18.
Consider an estimation problem of a linear combination of population means in a multivariate normal distribution under LINEX loss function. Necessary and sufficient conditions for linear estimators to be admissible are given. Further, it is shown that the result is an extension of the quadratic loss case as well as the univariate normal case.  相似文献   

19.
20.
Abstract.  A new kernel distribution function (df) estimator based on a non-parametric transformation of the data is proposed. It is shown that the asymptotic bias and mean squared error of the estimator are considerably smaller than that of the standard kernel df estimator. For the practical implementation of the new estimator a data-based choice of the bandwidth is proposed. Two possible areas of application are the non-parametric smoothed bootstrap and survival analysis. In the latter case new estimators for the survival function and the mean residual life function are derived.  相似文献   

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