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21.
This article reviews symmetrical global sensitivity analysis based on the analysis of variance of high-dimensional model representation. To overcome the computational difficulties and explore the use of symmetrical design of experiment (SDOE), two methods are presented. If the form of the objective function f is known, we use SDOE to estimate the symmetrical global sensitivity indices instead of Monte Carlo or quasi-Monte Carlo simulation. Otherwise, we use the observed values of the experiment to do symmetrical global sensitivity analysis. These methods are easy to implement and can reduce the computational cost. An example is given by symmetrical design of experiment. 相似文献
22.
In this paper, we consider the problem of making statistical inference for a truncated normal distribution under progressive type I interval censoring. We obtain maximum likelihood estimators of unknown parameters using the expectation-maximization algorithm and in sequel, we also compute corresponding midpoint estimates of parameters. Estimation based on the probability plot method is also considered. Asymptotic confidence intervals of unknown parameters are constructed based on the observed Fisher information matrix. We obtain Bayes estimators of parameters with respect to informative and non-informative prior distributions under squared error and linex loss functions. We compute these estimates using the importance sampling procedure. The highest posterior density intervals of unknown parameters are constructed as well. We present a Monte Carlo simulation study to compare the performance of proposed point and interval estimators. Analysis of a real data set is also performed for illustration purposes. Finally, inspection times and optimal censoring plans based on the expected Fisher information matrix are discussed. 相似文献
23.
目前遗传资源和传统知识法律保护机制国际探索的成就与不足——评CBD事先知情同意机制和FAO农民权机制 总被引:6,自引:0,他引:6
严永和 《贵州大学学报(社会科学版)》2006,24(3):31-36
传统知识是长期以来传统部族在长期的生产生活实践中创造出来的知识、技术、经验的总称,是一种知识形态和知识产品。CBD等国际组织对遗传资源及有关传统知识的保护进行了多年的探索,在保护机制上取得了一定的创新。CBD开创的事先知情同意机制和FAO开创的农民权机制为其代表。两种机制均在物权层面设计了遗传资源及有关传统知识的保护规则,但前者具有较强的保障力,后者基本上还是一种道义意义上的权利。但只有提供知识产权保护方能充分实现传统部族在传统知识上的利益。 相似文献
24.
Non-Gaussian spatial responses are usually modeled using spatial generalized linear mixed model with spatial random effects. The likelihood function of this model cannot usually be given in a closed form, thus the maximum likelihood approach is very challenging. There are numerical ways to maximize the likelihood function, such as Monte Carlo Expectation Maximization and Quadrature Pairwise Expectation Maximization algorithms. They can be applied but may in such cases be computationally very slow or even prohibitive. Gauss–Hermite quadrature approximation only suitable for low-dimensional latent variables and its accuracy depends on the number of quadrature points. Here, we propose a new approximate pairwise maximum likelihood method to the inference of the spatial generalized linear mixed model. This approximate method is fast and deterministic, using no sampling-based strategies. The performance of the proposed method is illustrated through two simulation examples and practical aspects are investigated through a case study on a rainfall data set. 相似文献
25.
Motivated by a recent tuberculosis (TB) study, this paper is concerned with covariates missing not at random (MNAR) and models the potential intracluster correlation by a frailty. We consider the regression analysis of right‐censored event times from clustered subjects under a Cox proportional hazards frailty model and present the semiparametric maximum likelihood estimator (SPMLE) of the model parameters. An easy‐to‐implement pseudo‐SPMLE is then proposed to accommodate more realistic situations using readily available supplementary information on the missing covariates. Algorithms are provided to compute the estimators and their consistent variance estimators. We demonstrate that both the SPMLE and the pseudo‐SPMLE are consistent and asymptotically normal by the arguments based on the theory of modern empirical processes. The proposed approach is examined numerically via simulation and illustrated with an analysis of the motivating TB study data. 相似文献
26.
There are now three essentially separate literatures on the topics of multiple systems estimation, record linkage, and missing
data. But in practice the three are intimately intertwined. For example, record linkage involving multiple data sources for
human populations is often carried out with the expressed goal of developing a merged database for multiple system estimation
(MSE). Similarly, one way to view both the record linkage and MSE problems is as ones involving the estimation of missing
data. This presentation highlights the technical nature of these interrelationships and provides a preliminary effort at their
integration. 相似文献
27.
Several models for studies related to tensile strength of materials are proposed in the literature where the size or length
component has been taken to be an important factor for studying the specimens’ failure behaviour. An important model, developed
on the basis of cumulative damage approach, is the three-parameter extension of the Birnbaum–Saunders fatigue model that incorporates
size of the specimen as an additional variable. This model is a strong competitor of the commonly used Weibull model and stands
better than the traditional models, which do not incorporate the size effect. The paper considers two such cumulative damage
models, checks their compatibility with a real dataset, compares them with some of the recent toolkits, and finally recommends
a model, which appears an appropriate one. Throughout the study is Bayesian based on Markov chain Monte Carlo simulation. 相似文献
28.
For capture–recapture models when covariates are subject to measurement errors and missing data, a set of estimating equations is constructed to estimate population size and relevant parameters. These estimating equations can be solved by an algorithm similar to the EM algorithm. The proposed method is also applicable to the situation when covariates with no measurement errors have missing data. Simulation studies are used to assess the performance of the proposed estimator. The estimator is also applied to a capture–recapture experiment on the bird species Prinia flaviventris in Hong Kong. The Canadian Journal of Statistics 37: 645–658; 2009 © 2009 Statistical Society of Canada 相似文献
29.
30.
The methods of estimation of nonparametric regression function are quite common in statistical application. In this paper, the new Bayesian wavelet thresholding estimation is considered. The new mixture prior distributions for the estimation of nonparametric regression function by applying wavelet transformation are investigated. The reversible jump algorithm to obtain the appropriate prior distributions and value of thresholding is used. The performance of the proposed estimator is assessed with simulated data from well-known test functions by comparing the convergence rate of the proposed estimator with respect to another by evaluating the average mean square error and standard deviations. Finally by applying the developed method, density function of galaxy data is estimated. 相似文献