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101.
An analytical expression is obtained for the marginal posterior density for a structural coefficient in a simultaneous equations system based on a limited information Bayesian analysis. A con- ditional posterior density is obtained given reduced form para- meters. This conditional posterior density is in univariate student t form. Numerical examples suggest that the conditional density hasa tighter distribution around the posterior mean than the unconditional density when the correlation between the endo- genous variables and the structural error term is high.  相似文献   
102.
This article presents a natural conjugate prior for the nonhomogeneous Poisson process (NHPP) with an exponential intensity function, for modeling the failure rate of repairable systems. The behavior of the conjugate prior distribution with respect to its parameters is studied, and the use of this prior in Bayesian estimation is compared to two other estimation approaches (the use of independent prior distributions, and the bivariate normal distribution). The use of the conjugate prior proposed here facilitates Bayesian statistical analysis of aging. In particular, the proposed prior allows us to explicitly account for dependence between the initial failure rate and the aging rate. This is a significant improvement over the assumptions made in most prior work (either the assumption that the aging rate is known, or the assumption that the initial failure rate and the aging rate are independent). Monte Carlo simulation shows that Bayesian estimation using the proposed prior generally performs at least as well as Bayesian estimation using independent priors for the initial failure rate and the aging rate,except in the case where the prior distribution underestimates both the initial failure rate and the aging rate.  相似文献   
103.
In this paper we consider two strategies for variation reduction. One of them is the exploitation of interactions. We also discuss the role of experiments in discovering interactions and in particular the use of robust designs to obtain the interaction between control and noise factors. Then we attempt to reduce the variation in a measurement system using a robust design.  相似文献   
104.
ABSTRACT

In this paper we study the classification of the generalized mixtures of two or three exponential distributions, in the ILR and DLR classes, and consequently in the IFR and DFR classes. We apply these results to classify the aging of the series and parallel systems, in accord with some common bivariate exponential models of their components.  相似文献   
105.
《随机性模型》2013,29(1):77-99
Abstract

In this paper, we present sufficient conditions, under which the stationary probability vector of a QBD process with both infinite levels and phases decays geometrically, characterized by the convergence norm η and the 1/η-left-invariant vector x of the rate matrix R. We also present a method to compute η and x based on spectral properties of the censored matrix of a matrix function constructed with the repeating blocks of the transition matrix of the QBD process. What makes this method attractive is its simplicity; finding η reduces to determining the zeros of a polynomial. We demonstrate the application of our method through a few interesting examples.  相似文献   
106.
《随机性模型》2013,29(2-3):643-668
Abstract

We investigate polynomial factorization as a classical analysis method for servers with semi-Markov arrival and service processes. The modeling approach is directly applicable to queueing systems and servers in production lines and telecommunication networks, where the flexibility in adaptation to autocorrelated processes is essential.

Although the method offers a compact form of the solution with favourable computation time complexity enabling to consider large state spaces and system equations of high degree, numerical stability is not guaranteed for this approach. Therefore we apply interval arithmetic in order to get verified results for the workload distributions, or otherwise to indicate that the precision of the computation has to be improved. The paper gives an overview of numerical and performance aspects of factorization in comparison to alternative methods.  相似文献   
107.
We develop an approach for estimating individual or household level preferences for a large set of quality-differentiated goods and for constructing Hicksian welfare measures within the demand system framework. Our approach uses a maximum simulated likelihood procedure to recover estimates of the structural parameters and a multistage, Monte Carlo Markov chain algorithm for constructing Hicksian consumer surplus estimates. We illustrate our approach with a recreation dataset consisting of day trips to 62 Mid-Atlantic beaches.  相似文献   
108.
王允武  王杰 《民族学刊》2013,4(4):71-79,123-127
2012年中国民族法学研究成果颇丰。其中,论文约有320余篇,比2011年增加了100余篇。这些研究在内容上有以下特点:一是内容较为全面,其中,民族习惯法、民族司法的研究比往年增多,民族政治权利成为年度重要话题;二是内容上的交叉研究增多;三是出现了一些综述性、反思性研究成果;四是关注了一些热点事件和话题;五是应用性研究成果较多。这些研究在方法上有以下特点:一是研究视角的多元化,协商民主成为年度新话题;二是注重实证研究;三是注重比较研究。在全面梳理的基础上,笔者根据研究内容所涉及的民族法学基本理论、民族权利保护、民族区域自治、民族法制建设、民族习惯法、民族法制史、民族司法等方面分别对其主要成果进行了介绍与评价,在辨别良莠、展示精华的同时,为不断繁荣中国民族法学提供可借鉴的年度综合性史料。  相似文献   
109.
在阐明可持续发展基本理论的基础上,根据省情,从经济、社会、资源、环境四方面构建湖北省可持续发展指标体系,针对小样本数据特点,运用灰色关联分析法、偏最小二乘回归对其可持续发展状况进行动态评价。  相似文献   
110.
中国宏观经济预警体系的评价与修正   总被引:2,自引:0,他引:2       下载免费PDF全文
石良平 《统计研究》2007,24(1):64-69
摘  要:中国宏观经济预警体系建立于20世纪90年代初,十多年来为国家宏观调控提供了可靠的信息,成为宏观调控的主要依据之一。然而,进入本世纪以来,中国经济的运行格局发生了重大变化,导致预警体系的敏感度和预测精度出现了偏差,已经到了需要修正的时候。本文在对中国宏观预警体系分析与评价的基础上,对体系的结构与指标提出了修正的思路与方案。  相似文献   
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