Inference and optimal design of multiple constant-stress testing for generalized half-normal distribution under type-II progressive censoring

The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion.     

Computing maximum likelihood estimates from type II doubly censored exponential data

It is well-known that, under Type II double censoring, the maximum likelihood (ML) estimators of the location and scale parameters, θ and δ, of a twoparameter exponential distribution are linear functions of the order statistics. In contrast, when θ is known, theML estimator of δ does not admit a closed form expression. It is shown, however, that theML estimator of the scale parameter exists and is unique. Moreover, it has good large-sample properties. In addition, sharp lower and upper bounds for this estimator are provided, which can serve as starting points for iterative interpolation methods such as regula falsi. Explicit expressions for the expected Fisher information and Cramér-Rao lower bound are also derived. In the Bayesian context, assuming an inverted gamma prior on δ, the uniqueness, boundedness and asymptotics of the highest posterior density estimator of δ can be deduced in a similar way. Finally, an illustrative example is included.     

坚持尊重社会发展规律与尊重人民历史主体地位的一致性——关于党的根本宗旨的哲学思考

把握党的根本宗旨 ,只有从历史规律实现的特殊性上理解人民的历史主体性与从人民的历史主体性上把握历史发展的规律的统一中 ,从马克思主义真理观是与价值观的统一中 ,才能深刻理解“党要始终代表中国最广大人民的根本利益”的真理性 ;实践党的根本宗旨 ,必须在坚持尊重社会发展规律与尊重人民历史主体地位的一致性的基础上 ,坚持为崇高理想奋斗与为最广大人民谋利益的一致性 ,坚持完成党的各项工作与实现人民利益的一致性 ,坚持一切为了人民群众与一切依靠人民群众的一致性。     

On Optimality of Bayesian Wavelet Estimators

Abstract.  We investigate the asymptotic optimality of several Bayesian wavelet estimators, namely, posterior mean, posterior median and Bayes Factor, where the prior imposed on wavelet coefficients is a mixture of a mass function at zero and a Gaussian density. We show that in terms of the mean squared error, for the properly chosen hyperparameters of the prior, all the three resulting Bayesian wavelet estimators achieve optimal minimax rates within any prescribed Besov space     for p  ≥ 2. For 1 ≤  p  < 2, the Bayes Factor is still optimal for (2 s +2)/(2 s +1) ≤  p  < 2 and always outperforms the posterior mean and the posterior median that can achieve only the best possible rates for linear estimators in this case.     

论唐湜的诗歌理论

唐湜诗歌评论的理论价值主要凸现在三个方面:一是在新诗的形式问题上,主张寓自由于格律之中,通过节奏与韵律来制约自由化,把自由化与格律化辩证统一起来;二是在新诗的审美追求上,认为新诗诗美的化境是走向意象的凝定;三是对诗歌含蓄美的倡导和肯定。这三个方面对于新诗的建设至今仍有现实意义。     

电子商务立法的国际比较及对我国的启示

电子商务的迅速发展实质性地改变了传统市场交易的形式。而作为法律调整和规范的主要对象之一，交易形式的变化要求有新的法律规定与之相适应。在国际上，关于电子商务的立法活动已经形成了一种浪潮。而我国的电子商务立法工作却一直进展缓慢。其中有认识上的问题，更主要的是立法经验的不足。借鉴有关国家电子商务立法的先进经验，我国应当尽快建立和完善电子商务法制，这其中包括应当建立关于电子签名、电子商务认证、电子合同、电子支付等方面的法律规则与制度。     

BAYESIAN SUBSET SELECTION AND MODEL AVERAGING USING A CENTRED AND DISPERSED PRIOR FOR THE ERROR VARIANCE

This article proposes a new data‐based prior distribution for the error variance in a Gaussian linear regression model, when the model is used for Bayesian variable selection and model averaging. For a given subset of variables in the model, this prior has a mode that is an unbiased estimator of the error variance but is suitably dispersed to make it uninformative relative to the marginal likelihood. The advantage of this empirical Bayes prior for the error variance is that it is centred and dispersed sensibly and avoids the arbitrary specification of hyperparameters. The performance of the new prior is compared to that of a prior proposed previously in the literature using several simulated examples and two loss functions. For each example our paper also reports results for the model that orthogonalizes the predictor variables before performing subset selection. A real example is also investigated. The empirical results suggest that for both the simulated and real data, the performance of the estimators based on the prior proposed in our article compares favourably with that of a prior used previously in the literature.     

企业会计模式的构建

现代企业制度是市场经济的基础,它要求建立与之相适应的会计模式.会计模式的建立受经济环境的制约,又要解决实际问题.在此分析的基础上,重点从客观经济环境和企业特点出发,从会计管理制度制定,会计信息系统设置和会计监督机制建立三大方面构建企业会计模式.     

Real nonparametric regression using complex wavelets

Summary.  Wavelet shrinkage is an effective nonparametric regression technique, especially when the underlying curve has irregular features such as spikes or discontinuities. The basic idea is simple: take the discrete wavelet transform of data consisting of a signal corrupted by noise; shrink or remove the wavelet coefficients to remove the noise; then invert the discrete wavelet transform to form an estimate of the true underlying curve. Various researchers have proposed increasingly sophisticated methods of doing this by using real-valued wavelets. Complex-valued wavelets exist but are rarely used. We propose two new complex-valued wavelet shrinkage techniques: one based on multiwavelet style shrinkage and the other using Bayesian methods. Extensive simulations show that our methods almost always give significantly more accurate estimates than methods based on real-valued wavelets. Further, our multiwavelet style shrinkage method is both simpler and dramatically faster than its competitors. To understand the excellent performance of this method we present a new risk bound on its hard thresholded coefficients.     

高校实验室管理与评估

本文阐述了在评估工作的推动下 ,如何加强对实验人员队伍建设、建立和完善各种规章制度的管理 ,并对实验室评估工作做了科学的总结。