A simulation study on power comparisons for group sequential tests of non-parametric statistics

In this article, a group sequential test (GST) of non-parametric statistics for survival data is briefly reviewed. An asymptotic joint distribution of the test statistics, obtained after each interim analysis, is given to illustrate the applicability of the critical values of the GST procedures. It should be noted that censored observations are generally seen in survival data. Therefore, if one makes power calculations irrespective of censoring, reliable results may not be achieved, due to the lack of information about the censoring structure. A wide simulation study, covering different censoring rates and tied observations, is conducted to make the power comparisons under various scenarios. The simulation results are interpreted and compared with the results obtained by using power analysis and sample size (PASS) software.     

A survey of permutation tests for censored survival data

The present paper surveys tests with censored sur-vival data for 2-and k-samples and for association by a framework which classifies them into complete or restric-ted permutation tests and into tests based on U-or Savage-scores. The formulae of the resulting twelve tests are briefly described for quick reference. Some of the tests have been applied frequently in the past as the tests by Mantel, Breslow or Gehan; others have been developed rather recently, partly by the author. The concluding discussion presents the results of a simulation study, clarifying similarities and differences of the restricted and complete permutation approach, and deals with rela-tive efficiencies of the two scoring systems.     

乡土世界中的女性悲歌——萧红小说中底层女性的生存悲剧

崛起于30年代的萧红就像一颗灿烂耀眼的新星在中国现代文坛上大放异彩。在她的文学创作中，是从女性的生育苦难和爱情、婚姻悲剧三方面来展现北方农村底层妇女的生存悲剧，从而阐释出女性在男权话语系统下的卑下地位。而这种别具风格的叙说方式与萧红自身的生命体验有着极其密切的联系。     

Semiparametric median residual life model and inference

For randomly censored data, the authors propose a general class of semiparametric median residual life models. They incorporate covariates in a generalized linear form while leaving the baseline median residual life function completely unspecified. Despite the non‐identifiability of the survival function for a given median residual life function, a simple and natural procedure is proposed to estimate the regression parameters and the baseline median residual life function. The authors derive the asymptotic properties for the estimators, and demonstrate the numerical performance of the proposed method through simulation studies. The median residual life model can be easily generalized to model other quantiles, and the estimation method can also be applied to the mean residual life model. The Canadian Journal of Statistics 38: 665–679; 2010 © 2010 Statistical Society of Canada     

On the moment generating functions for integer valued random variables

Abstract

In this note, we give explicit expressions of moment generating functions for integer valued random variables in both univariate and multivariate cases, which extend the results obtained by Nadarajah and Mitov [Communications in Statistics–Theory and Methods, 32, 2003, 47–60] and more recently by Chakraborti, Jardim and Epprecht [The American Statistician, 2017], Kwong and Nadarajah [Communications in Statistics–Theory and Methods, 2017]. Some examples are also discussed.     

生存智慧--人类与自然的和谐相处

人类现实地生活在四维时空的阳性物质世界,但是又与四维以上的多维时空的阴性物质世界有着天然的联系.这种联系除了生命的五大要素中有80%的部分存在于阴性物质世界之外,还有一个重要的方面,就是阴阳两个物质世界的生命存在形式在一定条件下相互转化,同时这两种生命存在形式又保持着动态的平衡,即出生人口和死亡人口大体上保持一定的比例.在自然界,动物的生存数量自动地保持着动态平衡,其中必有深刻的不为人们所知的原因.目前世界人口的膨胀已经使阴阳两种生命的存在形式严重失衡,也使人口的生产与物质资料的生产严重失调,因而造成了一系列灾难的发生.人类要增长生存智慧,借助科学的力量克服横在我们面前的一切困难,特别是要学会与自然界和谐相处,做到可持续发展.     

适者生存——简析《飘》的主题

本文拟就长篇小说《飘》中的四大主角在南北战争爆发后的不同反应和命运,展开主题讨论。斯卡利特与雷特代表了一种新的价值观念;而梅拉尼与阿什利则代表了一种旧的价值观念。在新旧观念的碰撞中,只有适者生存。这一生存原则在我们所处的这个社会转型期和时代转折点有其现实意义,因为在社会转型时期,社会竞争加剧,人们感到了前所未有的生存压力以及精神危机。     

徐州柳琴戏的生存现状与对策

以徐州柳琴戏作为研究对象,对其生存和发展进行剖析。柳琴戏是当地文化的一种选择,同时,柳琴戏也要适应本地区文化的要求。     

Empirical likelihood inference for the regression model of mean quality‐adjusted lifetime with censored data

The authors consider the empirical likelihood method for the regression model of mean quality‐adjusted lifetime with right censoring. They show that an empirical log‐likelihood ratio for the vector of the regression parameters is asymptotically a weighted sum of independent chi‐squared random variables. They adjust this empirical log‐likelihood ratio so that the limiting distribution is a standard chi‐square and construct corresponding confidence regions. Simulation studies lead them to conclude that empirical likelihood methods outperform the normal approximation methods in terms of coverage probability. They illustrate their methods with a data example from a breast cancer clinical trial study.