Accurate computation of single and product moments of order statistics under progressive censoring

An accurate procedure is proposed to calculate approximate moments of progressive order statistics in the context of statistical inference for lifetime models. The study analyses the performance of power series expansion to approximate the moments for location and scale distributions with high precision and smaller deviations with respect to the exact values. A comparative analysis between exact and approximate methods is shown using some tables and figures. The different approximations are applied in two situations. First, we consider the problem of computing the large sample variance–covariance matrix of maximum likelihood estimators. We also use the approximations to obtain progressively censored sampling plans for log-normal distributed data. These problems illustrate that the presented procedure is highly useful to compute the moments with precision for numerous censoring patterns and, in many cases, is the only valid method because the exact calculation may not be applicable.     

Stress-strength reliability of exponentiated Fréchet distributions based on Type-II censored data

In this paper, we consider inference of the stress-strength parameter, R, based on two independent Type-II censored samples from exponentiated Fréchet populations with different index parameters. The maximum likelihood and uniformly minimum variance unbiased estimators, exact and asymptotic confidence intervals and hypotheses testing for R are obtained. We conduct a Monte Carlo simulation study to evaluate the performance of these estimators and confidence intervals. Finally, two real data sets are analysed for illustrative purposes.     

Progressive censoring with fixed censoring times

In this paper, we revisit the progressive Type-I censoring scheme as it has originally been introduced by Cohen [Progressively censored samples in life testing. Technometrics. 1963;5(3):327–339]. In fact, original progressive Type-I censoring proceeds as progressive Type-II censoring but with fixed censoring times instead of failure time based censoring times. Apparently, a time truncation has been added to this censoring scheme by interpreting the final censoring time as a termination time. Therefore, not much work has been done on Cohens's original progressive censoring scheme with fixed censoring times. Thus, we discuss distributional results for this scheme and establish exact distributional results in likelihood inference for exponentially distributed lifetimes. In particular, we obtain the exact distribution of the maximum likelihood estimator (MLE). Further, the stochastic monotonicity of the MLE is verified in order to construct exact confidence intervals for both the scale parameter and the reliability.     

On the power of goodness-of-fit tests for the exponential distribution under progressive Type-II censoring

The aim of this article is to review existing goodness-of-fit tests for the exponential distribution under progressive Type-II censoring and to provide some new ideas and adjustments. In particular, we consider two-parameter exponentially distributed random variables and adapt the proposed test procedures to our scenario if necessary. Then, we compare their power by an extensive simulation study. Furthermore, we propose five new test procedures that provide reasonable alternatives to those already known.     

Estimating E-bayesian and hierarchical bayesian of scalar parameter of gompertz distribution under type II censoring schemes based on fuzzy data

In this study, the E-Bayesian and hierarchical Bayesian of the scalar parameter of a Gompertz distribution under Type II censoring schemes were estimated based on fuzzy data under the squared error (SE) loss function and the efficiency of the proposed methods was compared with each other and with the Bayesian estimator using Monte Carlo simulation.     

Prediction of future failures times based on Type-I hybrid censored samples of random sample sizes

In this article, we consider the prediction of future failure times based on Type-I hybrid censored samples. Point predictors and prediction intervals using different procedures are discussed for a general model. The exponential and Rayleigh distributions are used as illustrative examples to show the most simplified forms of the so obtained predictors as well as prediction intervals. Intensive simulation study and a real life dataset are presented to illustrate our findings and results.     

A volume based approach to establish B-spline based expressions for density functions and its application to progressive hybrid censoring

We propose an approach to determine the distribution of particular linear combinations of hybrid censored order statistics which is based on the calculation of volumes of polytopes. For this purpose, we establish efficient and compact volume formulas in terms of B-splines. Further, we illustrate our approach for ten different progressive hybrid censoring schemes under an exponential assumption.     

社会学民族志的力量:重返早期社会研究的田野工作

自20世纪70年代以来,社会学民族志在田野工作和叙事复兴中与传统人文学汇聚,显著扩展了自己的学科边界。但是,这种扩展并没有解决社会学民族志在深度的经验发生和强烈的理论诉求之间遭遇的紧张。对于这种紧张,本文主张再访早期社会研究的田野,即19世纪末期到一战之前的若干典型研究,从中反思早期社会学田野工作是如何在“直接经验”的倾向中完成类型化,以及如何在这个经验感获得的同时改变对社会世界的道德想象。早期社会学的田野工作的力量之一不在于以规范的诉求压制经验感,而是以独特的情感结构连接经验的观察和道德理想的重生。由此,我们不仅需要反思诸如社会调查到社区研究这样的简单思路,更要重新理解理论史上所谓的“进步主义式”的道德本身。这一工作对重新认识早期社会研究和今天的社会学民族志都具有意义上的准备。     

论行政法规之审查基准

审查基准是行政法规审查制度的重要组成部分,它不仅规定了行政法规合法性审查之宽严程度,也限定了审查机关之权限范围。根据我国宪法与立法法之规定,全国人民代表大会常务委员会对行政法规之审查以"合法性"为基准。这种"合法性"审查基准在行政法规制定权限审查、行政法规内容审查以及审查程序等方面遭遇现实难题,并因此净化了行政法规审查制度的现实效果,为此,有必要引借"合理性"审查基准,并借此推动我国行政法规审查制度的完善。     

对虚假广告行为的规制

在我国,虚假广告已成公害,造成这种状况的原因之一是我国有关广告的现行立法存在缺陷。为有效遏止虚假广告行为,切实保护消费者的合法权益,维护市场主体的公平竞争,借鉴国外立法例,我国应明确界定虚假广告的法律概念,改革广告审查制度,加大对虚假广告行为的处罚力度,并注意立法的协调性和统一性。