Variable screening for survival data in the presence of heterogeneous censoring

Variable screening for censored survival data is most challenging when both survival and censoring times are correlated with an ultrahigh-dimensional vector of covariates. Existing approaches to handling censoring often make use of inverse probability weighting by assuming independent censoring with both survival time and covariates. This is a convenient but rather restrictive assumption which may be unmet in real applications, especially when the censoring mechanism is complex and the number of covariates is large. To accommodate heterogeneous (covariate-dependent) censoring that is often present in high-dimensional survival data, we propose a Gehan-type rank screening method to select features that are relevant to the survival time. The method is invariant to monotone transformations of the response and of the predictors, and works robustly for a general class of survival models. We establish the sure screening property of the proposed methodology. Simulation studies and a lymphoma data analysis demonstrate its favorable performance and practical utility.     

The Introduction of Matrix Algebra into Statistics

Primary credit for the introduction of matrix algebra into statistics is given to A. C. Aitken in the 1930s.     

构建我国顶岗实习工伤保险制度的法律思考

我国有关顶岗实习工伤的立法存在诸多缺陷,导致实践中的困惑,且对顶岗实习各方的权益保护不足,不利于社会和谐。工伤保险模式是必然的选择,在将顶岗实习工伤纳入工伤保险制度时,应考虑其特殊性,做出变通性规定。     

燃油税实施效果评价——基于北京地区的调查报告

2009年1月1日起,燃油税开始在全国范围内征收.燃油税改革关系重大,涉及中国多数的企业、家庭和住户的工作与生活,本研究报告对燃油税改革的实施效果进行快速跟踪调查,一方面作为对这项政策实施效果的回馈,另一方面则希望能够通过公众的反映以及对实际状况的分析来为政策实施过程中可能出现的问题提出解决的思路.     

Optimal robust influence functions in semiparametric regression

Robust statistics allows the distribution of the observations to be any member of a suitable neighborhood about an ideal model distribution. In this paper, the ideal models are semiparametric with finite-dimensional parameter of interest and a possibly infinite-dimensional nuisance parameter.In the asymptotic setup of shrinking neighborhoods, we derive and study the Hampel-type problem and the minmax MSE-problem. We show that, for all common types of neighborhood systems, the optimal influence function can be approximated by the optimal influence functions for certain parametric models.For general semiparametric regression models, we determine in case of error-in-variables and in case of error-free-variables.Finally, the results are applied to Cox regression where we compare our approach to that of Bednarski [1993. Robust estimation in Cox's regression model. Scand. J. Statist. 20, 213–225] in a small simulation study and on a real data set.     

Parameter estimation of the generalized Pareto distribution—Part II

This is the second part of a paper which focuses on reviewing methods for estimating the parameters of the generalized Pareto distribution (GPD). The GPD is a very important distribution in the extreme value context. It is commonly used for modeling the observations that exceed very high thresholds. The ultimate success of the GPD in applications evidently depends on the parameter estimation process. Quite a few methods exist in the literature for estimating the GPD parameters. Estimation procedures, such as the maximum likelihood (ML), the method of moments (MOM) and the probability weighted moments (PWM) method were described in Part I of the paper. We shall continue to review methods for estimating the GPD parameters, in particular methods that are robust and procedures that use the Bayesian methodology. As in Part I, we shall focus on those that are relatively simple and straightforward to be applied to real world data.     

Association of progressively Type-II censored order statistics

The association of progressively Type-II censored order statistics from a sample of associated random variables _X1,…,_Xn$X_1,\dots ,X_n$ is established. Moreover, some bivariate dependence properties are discussed for independent but not necessarily identically distributed _X1,…,_Xn$X_1,\dots ,X_n$.     

中国经济统计学科建设30年回顾与评论 ——-基于三大事件框架的研究

 本文将我国经济统计学科30年的建设历史梳理归纳为三件事,即统计学科性质与大统计学科构建的争论,统计改革推动学科的研究创新,学科建设机制的构筑。以这三件事对学科建设的影响评价为基础,建立分析框架。基于30年历史文献的回顾、解读、分析,提出了若干促进我国经济统计学建设的新思考、新观点,希望能供学科发展的未来借鉴。     

《中国统计年鉴》：政府统计窗口建设的回顾与展望

《中国统计年鉴》是显示中国发展状况的窗口,也是显示中国政府统计能力的窗口。本文以纵向历史变化为主线,首先回顾了《年鉴》从无到有和后续演变的全过程,着力发掘变化背后的原因和力量;然后着眼未来建设,对《年鉴》的内容架构和基本定位做了比较深入的讨论。