区域微电子技术发展实力综合评价研究

本文运用模糊数学方法,建立了多层次模糊综合评判模型。并根据实际情况选用不同算子,对中国区域微电子技术发展实力进行了综合评价,为有关部门制订微电子技术区域发展政策提供了参考。     

Adaptive interval estimation in one-way random effects models

Two-stage procedures are introduced to control the width and coverage (validity) of confidence intervals for the estimation of the mean, the between groups variance component and certain ratios of the variance components in one-way random effects models. The procedures use the pilot sample data to estimate an “optimal” group size and then proceed to determine the number of groups by a stopping rule. Such sampling plans give rise to unbalanced data, which are consequently analyzed by the harmonic mean method. Several asymptotic results concerning the proposed procedures are given along with simulation results to assess their performance in moderate sample size situations. The proposed procedures were found to effectively control the width and probability of coverage of the resulting confidence intervals in all cases and were also found to be robust in the presence of missing observations. From a practical point of view, the procedures are illustrated using a real data set and it is shown that the resulting unbalanced designs tend to require smaller sample sizes than is needed in a corresponding balanced design where the group size is arbitrarily pre-specified.     

Exact inference for a simple step-stress model with competing risks for failure from exponential distribution under Type-II censoring

In reliability analysis, accelerated life-testing allows for gradual increment of stress levels on test units during an experiment. In a special class of accelerated life tests known as step-stress tests, the stress levels increase discretely at pre-fixed time points, and this allows the experimenter to obtain information on the parameters of the lifetime distributions more quickly than under normal operating conditions. Moreover, when a test unit fails, there are often more than one fatal cause for the failure, such as mechanical or electrical. In this article, we consider the simple step-stress model under Type-II censoring when the lifetime distributions of the different risk factors are independently exponentially distributed. Under this setup, we derive the maximum likelihood estimators (MLEs) of the unknown mean parameters of the different causes under the assumption of a cumulative exposure model. The exact distributions of the MLEs of the parameters are then derived through the use of conditional moment generating functions. Using these exact distributions as well as the asymptotic distributions and the parametric bootstrap method, we discuss the construction of confidence intervals for the parameters and assess their performance through Monte Carlo simulations. Finally, we illustrate the methods of inference discussed here with an example.     

依托渝怀铁路实施以路兴区发展战略

结合渝怀线的现有资源和经济状况，采用定性和定量相结合的方法分析了渝怀经济带在西部大开发中的地位、作用及近远期发展战略和思路。     

西部股票市场绩效研究与发展建议

研究西部股票市场对西部经济发展的作用与影响，认为提高西部股票市场的运作效率，有助于促进西部投资的增长。研究结果表明，要解决西部资金短缺状况，必须加快西部经济货币化进程，大力培育西部股票市场。     

Improved Estimates and Confidence Intervals for Regenerative Simulation

In regenerative simulation, one frequently requires an estimate or a confidence interval for the ratio of the means of the two components of a certain bivariate random quantity. Estimation of this ratio has been studied by many authors and most recently by Asmussen and Rydén(2010 Asmussen, S., Rydén, T. (2010). A note on skewness in regenerative simulation. Communications in Statistics—Simulation and Computation 40: 45–57.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]). Here, we propose an estimate that performs better than the best of the known estimates. Our estimate is also lot simpler than the best known estimate.     

西部农村消费需求的边际倾向与收入弹性比较分析

收入是拉动消费需求增加的非常重要的动力,但在我国,由于地域差异大,经济一直落后的西部农村地区,收入虽然也有所增加,但由于经济基础薄弱而使收入的增加对消费增加的作用不明显,消费的边际倾向和收入弹性相对东部地区的省份高,所以进一步增加西部农民的收入就很容易启动潜在消费,从而刺激全国的有效需求,使我国经济尽快走出低迷的状态。     

西北普通高校大学生体育锻炼意识与运动兴趣的调查研究

通过对西北普通高校大学生体育锻炼意识、健康状况与运动兴趣调查分析表明 :大学生喜欢上体育的人数不到 6 0 % ,相当一部分学生对体育的健身价值缺乏正确的认识 ,没有体育锻炼的习惯和意识 ;学生的体质健康状况不理想 ,必须引起有关领导的重视 ;学生对健身类、健美类、娱乐兴和球类体育活动比较感兴趣 ,学校应多为学生提供这方面的教学和活动场所。     

西部地区农村城镇化与人居环境建设

西部地区农村城镇人口和乡村工业的过度集中以及对自然资源开发强度的日益加大,使污染物排放量急剧增长,生态环境遭到破坏,农村城镇人居环境不断恶化。人居环境的恶化反过来又限制了西部农村经济的发展。因此,通过树立新的发展观、城镇规划要注意对生态环境的保护、开展农村城镇居民绿色住宅工程、发展生态农业和环保产业等措施,以良好的农村城镇人居环境推动西部地区经济的持续、协调和稳步发展。     

Exact Likelihood Inference for k Exponential Populations Under Joint Type-II Censoring

In this paper, when a jointly Type-II censored sample arising from k independent exponential populations is available, the conditional MLEs of the k exponential mean parameters are derived. The moment generating functions and the exact densities of these MLEs are obtained using which exact confidence intervals are developed for the parameters. Moreover, approximate confidence intervals based on the asymptotic normality of the MLEs and credible confidence regions from a Bayesian viewpoint are also discussed. An empirical comparison of the exact, approximate, bootstrap, and Bayesian intervals is also made in terms of coverage probabilities. Finally, an example is presented in order to illustrate all the methods of inference developed here.