Sample size re‐estimation incorporating prior information on a nuisance parameter

Prior information is often incorporated informally when planning a clinical trial. Here, we present an approach on how to incorporate prior information, such as data from historical clinical trials, into the nuisance parameter–based sample size re‐estimation in a design with an internal pilot study. We focus on trials with continuous endpoints in which the outcome variance is the nuisance parameter. For planning and analyzing the trial, frequentist methods are considered. Moreover, the external information on the variance is summarized by the Bayesian meta‐analytic‐predictive approach. To incorporate external information into the sample size re‐estimation, we propose to update the meta‐analytic‐predictive prior based on the results of the internal pilot study and to re‐estimate the sample size using an estimator from the posterior. By means of a simulation study, we compare the operating characteristics such as power and sample size distribution of the proposed procedure with the traditional sample size re‐estimation approach that uses the pooled variance estimator. The simulation study shows that, if no prior‐data conflict is present, incorporating external information into the sample size re‐estimation improves the operating characteristics compared to the traditional approach. In the case of a prior‐data conflict, that is, when the variance of the ongoing clinical trial is unequal to the prior location, the performance of the traditional sample size re‐estimation procedure is in general superior, even when the prior information is robustified. When considering to include prior information in sample size re‐estimation, the potential gains should be balanced against the risks.     

岩石可钻性能量法现场实验研究

本文介绍了岩石可钻性能全法在油田现场实脸研究的成果:确定其可钻性指标凡对地层的适用范围，证明K指标比其他可钻性指标能更容易、史好地反映出井下实际地层可钻性变化情无，用K指标预浏钻速与实际钻速接近.     

Transition probabilities and ARL performance of Six Sigma zone control charts

In this article, Six Sigma zone control charts (SSZCCs) are proposed for world class organizations. The transition probabilities are obtained using the Markov chain approach. The Average Run Length (ARL) values are then presented. The ARL performance of the proposed SSZCCs and the standard Six Sigma control chart (SSCC) without zones or run rules is studied. The ARL performance of these charts is then compared with those of the other standard zone control charts (ZCCs), the modified ZCC and the traditional Shewhart control chart (SCC) with common run rules. As expected, it is shown that the proposed SSZCC outperforms the standard SSCC without zones or run rules for process shifts of any magnitude. When compared to the other standard ZCCs and the Shewhart chart with common run rules, it is observed that the proposed SSZCCs have much higher false alarm rates for smaller shifts and hence they prevent unwanted process disturbances. The application of the proposed SSZCC is illustrated using a real time example.     

Is there a global super-bourgeoisie?

In recent decades, accelerating processes of globalization and an increase in economic inequality in most of the world's countries have raised the question of the emergence of a new bourgeoisie integrated at the global level, sometimes described as a global super-bourgeoisie. This group would be distinguished by its unequaled level of wealth and global interconnectedness, its transnational ubiquity and concentration in the planet's major global cities, its specific culture, consumption habits, sites of sociability and shared references, and even by class consciousness and capacity to act collectively. This article successively discusses how the social sciences have examined these various dimensions of the question and begun to provide systematic empirical answers.     

Modelling financial satisfaction across life stages: A latent class approach

We explore the determinants of financial satisfaction using a modelling framework which allows the drivers of financial satisfaction to vary across life stages. Given that financial satisfaction is measured as an ordered variable, our modelling approach is based on a latent class ordered probit model with an ordered probit class assignment function. Our analysis of household survey data indicates that four life stages are supported by the data. Our results suggest that such flexibility is important in understanding the drivers of financial satisfaction over the life cycle since there is a substantial amount of parameter heterogeneity across the four classes.     

大学思想政治理论课课堂教学改革新思路

思想政治理论课是大学生思想政治教育的主渠道,而课堂教学在主渠道的畅通中承担着主要的任务。针对课堂教学存在的诸多问题,教学改革尤为迫切。深入调查研究,及时掌握和分析大学生的各种信息是教学改革最为基础性的工作;树立以生为本理念,课堂教学追求多样性实效性是教学改革的外在表现;教书育人,当好大学生健康成长的指导者和引路人则是思想政治理论课教师的根本职责和庄严使命。     

Pollutant Ground Concentrations of Nonneutrally Buoyant Particles

A methodology is suggested for the estimation of the mass density and the cumulative ground deposition of a nonvolatile, nonneutrally buoyant, air pollutant (liquid or solid) released from a polluted column (following an explosion caused during routine operation in, e.g., the chemical industry or due to any kind of hostile act) and deposited on the ground via gravitational settling. In many cases, the deposited mass due to gravitational settling constitutes a significant fraction of the original inventory released from the source. Implementation of the methodology in preliminary risk assessments can serve as an efficient tool for emergency planning for both immediate and long‐term measures such as evacuation and decontamination. The methodology considers, inter alia, an estimation of the critical particle diameter, particle size, and mass distributions along the polluted column. This methodology was developed to apply in rural regions since proper application of relevant meteorological input data can be accomplished mainly for such areas.     

基于邻避运动视域的中产阶层功能重新审视]——以R市的“核邻避运动”为例

国内学术界将“中产阶层”视为社会政治“稳定—缓冲”器的认知看似符合静态的中国社会结构，但就现实而言，却忽略了转型期中国政治社会情境的复杂性和过渡性。近年来，城市中产业主引发的愈演愈烈的邻避运动，更是挑战这一传统认知。基于R市“核邻避运动”的视域，我们发现中国城市中产阶层的社会政治功能在某一特定时间流下会发生转变，甚至出现了“稳定器”和“动荡器”两个相对立的社会、政治功能。而差别阶层特质、中产精英上台等内部中介机制,以及怨愤情绪生产、政府内部分歧等外部中介机制，是中产阶层社会政治功能演化的深层机制。此外，值得注意的是，由于“身份限制”和“制度限制”的二重性，中产阶层的社会政治功能往往并不会演变为“颠覆—异化”器。     

Pre-term Foetal Life Times in Scotland

A proportional hazards model was used to evaluate the association between ten categorical covariates and the risk of pre-term delivery for women having their first child and women in subsequent pregnancies. An adaptation of the model for use with grouped survival times made it possible to model foetal life times between 28 and 36 completed weeks of gestation for 67,000 Scottish singleton births in 1981. The use of the model was justified by testing time-dependent effects. For both groups of women age, and a history of abortion, were major factors associated with increased hazard. For women experiencing a second or higher-order birth a history of perinatal death was also associated with substantially increased hazard to the pregnancy.