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Hypothesis Testing with Paired Partly Interval Censored Data
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作者 Ding-jiao CAI Bo LU Xing-wei TONG 《应用数学学报:英文版》 SCIE CSCD 2019年第3期541-548,共8页
Partly interval censored data frequently occur in many areas including clinical trials,epidemiology research,and medical follow-up studies.When data come from observational studies,we need to carefully adjust for the ... Partly interval censored data frequently occur in many areas including clinical trials,epidemiology research,and medical follow-up studies.When data come from observational studies,we need to carefully adjust for the confounding bias in order to estimate the true treatment effect.Pair matching designs are popular for removing confounding bias without parametric assumptions.With time-to-event outcomes,there are some literature for hypothesis testing with paired right censored data,but not for interval censored data.O’Brien and Fleming extended the Prentice Wilcoxon test to right censored paired data by making use of the PrenticeWilcoxon scores.Akritas proposed the Akritas test and established its asymptotic properties.We extend Akritas test to partly interval censored data.We estimate the survival distribution function by nonparametric maximum likelihood estimation(NPMLE),and prove the asymptotic validity of the new test.To improve our test under small sample size or extreme distributions,we also propose a modified version using the rank of the score difference.Simulation results indicate that our proposed methods have very good performance. 展开更多
关键词 partly INTERVAL censored data NONPARAMETRIC MAXIMUM LIKELIHOOD estimation Wilcoxon SIGNED RANK test
区间删失下恒定应力部分加速寿命试验的统计分析(英文) 预览
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作者 龙兵 张忠占 《数学季刊:英文版》 2019年第1期1-13,共13页
In this paper, a statistical analysis method is proposed to research life characteristics of products based on the partially accelerated life test. We discuss the statistical analysis for constant-stress partially acc... In this paper, a statistical analysis method is proposed to research life characteristics of products based on the partially accelerated life test. We discuss the statistical analysis for constant-stress partially accelerated life tests with Lomax distribution based on interval censored samples. The EM algorithm is used to obtain the maximum likelihood estimations(MLEs) and interval estimations for the shape parameter and acceleration factor.The average relative errors(AREs), mean square errors(MSEs), the confidence intervals for the parameters, and the influence of the sample size are discussed. The results show that the AREs and MSEs of the MLEs decrease with the increase of sample size. Finally, a simulation sample is used to estimate the reliability under different stress levels. 展开更多
关键词 INTERVAL censored samples PARTIALLY ACCELERATED life test ACCELERATED factor EM algorithm FISHER information matrix
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Bayesian empirical likelihood and variable selection for censored linear model with applications to acute myelogenous leukemia data
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作者 Chun-Jing Li Hong-Mei Zhao Xiao-Gang Dong 《生物数学学报:英文版》 2019年第5期43-61,共19页
This paper develops the Bayesian empirical likelihood (BEL) method and the BEL vari-able selection for linear regression models with censored data.Empirical likelihood is a multivariate analysis tool that has been wid... This paper develops the Bayesian empirical likelihood (BEL) method and the BEL vari-able selection for linear regression models with censored data.Empirical likelihood is a multivariate analysis tool that has been widely applietl to many fieltls such as biomed-ical and social sciences.By introducing two special priors to the empirical likelihood function,we find two obvious superiorities of the BEL methods,that is (i) more precise coverage probabilities of the BEL credible region and (ii) higher accuracy and correct identification rate of the BEL model selection using an hierarchical Bayesian models vs.some current methods such as the LASSO,A LASSO and SCAD.The numerical simu-lations and empirical analysis of two data examples show strong competitiveness of the proposed method. 展开更多
关键词 BAYESIAN empirical likeliliood censored linear regression COVERAGE probabili-ties spike-and-slab prior
Feature Screening for Ultrahigh-dimensional Censored Data with Varying Coefficient Single-index Model
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作者 Yi LIU 《应用数学学报:英文版》 CSCD 2019年第4期845-861,共17页
In this paper, we study the sure independence screening of ultrahigh-dimensional censored data with varying coefficient single-index model. This general model framework covers a large number of commonly used survival ... In this paper, we study the sure independence screening of ultrahigh-dimensional censored data with varying coefficient single-index model. This general model framework covers a large number of commonly used survival models. The property that the proposed method is not derived for a specific model is appealing in ultrahigh dimensional regressions, as it is difficult to specify a correct model for ultrahigh dimensional predictors.Once the assuming data generating process does not meet the actual one, the screening method based on the model will be problematic. We establish the sure screening property and consistency in ranking property of the proposed method. Simulations are conducted to study the finite sample performances, and the results demonstrate that the proposed method is competitive compared with the existing methods. We also illustrate the results via the analysis of data from The National Alzheimers Coordinating Center(NACC). 展开更多
关键词 censored data consistency in ranking PROPERTY FEATURE selection HIGH-DIMENSIONAL data sure SCREENING PROPERTY VARYING COEFFICIENT single-index model
Evaluation of TIGGE Daily Accumulated Precipitation Forecasts over the Qu River Basin,China
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作者 Li LIU Chao GAO +1 位作者 Qian ZHU Yue-Ping XU 《气象学报:英文版》 SCIE CSCD 2019年第4期747-764,共18页
Quantitative precipitation forecasts(QPFs)provided by three operational global ensemble prediction systems(EPSs)from the THORPEX(The Observing System Research and Predictability Experiment)Interactive Grand Global Ens... Quantitative precipitation forecasts(QPFs)provided by three operational global ensemble prediction systems(EPSs)from the THORPEX(The Observing System Research and Predictability Experiment)Interactive Grand Global Ensemble(TIGGE)archive were evaluated over the Qu River basin,China during the plum rain and typhoon seasons of 2009–13.Two post-processing methods,the ensemble model output statistics based on censored shifted gamma distribution(CSGD-EMOS)and quantile mapping(QM),were used to reduce bias and to improve the QPFs.The results were evaluated by using three incremental precipitation thresholds and multiple verification metrics.It is demonstrated that QPFs from NCEP and ECMWF presented similarly skillful forecasts,although the ECMWF QPFs performed more satisfactorily in the typhoon season and the NCEP QPFs were better in the plum rain season.Most of the verification metrics showed evident seasonal discriminations,with more satisfactory behavior in the plum rain season.Lighter precipitation tended to be overestimated,but heavier precipitation was always underestimated.The post-processed QPFs showed a significant improvement from the raw forecasts and the effects of post-processing varied with the lead time,precipitation threshold,and EPS.Precipitation was better corrected at longer lead times and higher thresholds.CSGD-EMOS was more effective for probabilistic metrics and the root-mean-square error.QM had a greater effect on removing bias according to bias and categorical metrics,but was unable to warrant reliabilities.In general,raw forecasts can provide acceptable QPFs eight days in advance.After post-processing,the useful forecasts can be significantly extended beyond 10 days,showing promising prospects for flood forecasting. 展开更多
关键词 TIGGE quantitative precipitation forecasts QUANTILE mapping censored shifted GAMMA distribution
Distribution Approximation of Shrinkage Estimate in Censored Regression Model via Randomly Weighting Method
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作者 Xian-hui LIU Zhan-feng WANG Yao-hua WU 《应用数学学报:英文版》 SCIE CSCD 2019年第2期421-434,共14页
Censored regression ("Tobit") model is a special case of limited dependent variable regression model, and plays an important role in econometrics. Based on this model, all kinds of methods for variable or gr... Censored regression ("Tobit") model is a special case of limited dependent variable regression model, and plays an important role in econometrics. Based on this model, all kinds of methods for variable or group variable selection have been developed and the corresponding shrinkage parameter estimates are widely studied. However, asymptotic distributions of the shrinkage estimates involve unknown nuisance parameters, such as density function of error term. To avoid estimating nuisance parameters, this paper presents a randomly weighting method to approximate to the asymptotic distribution of the shrinkage estimate. A computation procedure of random approximation is provided and asymptotic properties of the randomly weighting estimates are also obtained. The proposed methods are evaluated with extensively numerical studies and a women labor supply example. 展开更多
关键词 Censored regression model VARIABLE SELECTION ASYMPTOTIC properties randomly weighting
Inference and optimal design on step-stress partially accelerated life test for hybrid system with masked data 预览
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作者 SHI Xiaolin LU Pu SHI Yimin 《系统工程与电子技术:英文版》 SCIE EI CSCD 2018年第5期1089-1100,共12页
Under Type-II progressively hybrid censoring,this paper discusses statistical inference and optimal design on stepstress partially accelerated life test for hybrid system in presence of masked data.It is assumed that ... Under Type-II progressively hybrid censoring,this paper discusses statistical inference and optimal design on stepstress partially accelerated life test for hybrid system in presence of masked data.It is assumed that the lifetime of the component in hybrid systems follows independent and identical modified Weibull distributions.The maximum likelihood estimations(MLEs)of the unknown parameters,acceleration factor and reliability indexes are derived by using the Newton-Raphson algorithm.The asymptotic variance-covariance matrix and the approximate confidence intervals are obtained based on normal approximation to the asymptotic distribution of MLEs of model parameters.Moreover,two bootstrap confidence intervals are constructed by using the parametric bootstrap method.The optimal time of changing stress levels is determined under D-optimality and A-optimality criteria.Finally,the Monte Carlo simulation study is carried out to illustrate the proposed procedures. 展开更多
关键词 HYBRID system step-stress PARTIALLY ACCELERATED life TEST TYPE-II progressively HYBRID censored and masked data statistical INFERENCE optimal TEST plan
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Survival Analysis in Modeling the Birth Interval of the First Child in Indonesia 预览
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作者 Rahmat Hidayat Hadi Sumarno Endar H. Nugrahani 《统计学期刊(英文)》 2014年第3期198-206,共9页
First birth interval is one of the examples of survival data. One of the characteristics of survival data is its observation period that is fully unobservable or censored. Analyzing the censored data using ordinary me... First birth interval is one of the examples of survival data. One of the characteristics of survival data is its observation period that is fully unobservable or censored. Analyzing the censored data using ordinary methods will lead to bias, so that reducing such bias required a certain method called survival analysis. There are two methods used in survival analysis that are parametric and non-parametric method. The objective of this paper is to determine the appropriate method for modeling the birth of the first child. The exponential model with the inclusion of covariates is used as parametric method, considering that the newly married couples tend to have desire for having baby as soon as possible and such desire will be weakened by increasing age of marriage. The data that will be analyzed were taken from the Indonesia Demographic and Health Survey (IDHS) 2012. The result of data analysis shows that the birth of the first child data is not exponentially distributed thus the Cox proportional hazard method is used. Because of the suspicion that disproportional covariate exists, then the proportional hazard test is conducted to show that the covariate of age is not proportional, the generalized Cox proportional method is used, namely Cox extended that allows the inclusion of disproportional covariates. The result of analysis using Cox extended model indicates that the factors affecting the birth of the first child in Indonesia are the area of residence, educational history and its age. 展开更多
关键词 Analysis SURVIVAL Censored COVARIATE COX Proportional HAZARD COX EXTENDED
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中国能源效率测度及其影响因素分析 预览 被引量:8
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作者 周睿 《统计与决策》 CSSCI 北大核心 2014年第5期84-86,共3页
文章通过DEA-Censored Data模型分析框架,利用CCR模型和BCC模型分别测度了改革开放后中国近30年来的中国能源效率,并分析了诸如能源结构、所有制结构、产业结构等因素对其的影响
关键词 能源效率 CCR模型 BCC模型 Censored DATA模型
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截断非平衡似无关模型的极大仿真似然估计 被引量:1
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作者 陈永伟 葛翔宇 《系统工程理论与实践》 EI CSSCI CSCD 北大核心 2014年第3期732-737,共6页
样本数据缺失和截断是现代统计调查中经常遇到的两个问题,它们在一定程度上影响模型参数估计的准确性和有效性.该研究首先提出了一个新的截断非平衡似无关回归模型,这个模型能够同时考虑数据缺失和截断的特征;然后基于Geweke—Hajiv... 样本数据缺失和截断是现代统计调查中经常遇到的两个问题,它们在一定程度上影响模型参数估计的准确性和有效性.该研究首先提出了一个新的截断非平衡似无关回归模型,这个模型能够同时考虑数据缺失和截断的特征;然后基于Geweke—Hajivassiliou—Keane(GHK)的仿真算子,建立了该模型的极大仿真似然估计方法;蒙特卡罗实验结果表明,在大样本和有限样本下这种估计方法在参数估计的准确性和有效性方面均具有良好表现. 展开更多
关键词 似无关回归 截断 缺失 极大仿真似然估计
Nonparametric Demand Forecasting with Right Censored Observations 预览
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作者 Bin ZHANG Zhongsheng HUA 《软件工程与应用(英文)》 2009年第4期259-266,共8页
In a newsvendor inventory system, demand observations often get right censored when there are lost sales and no backordering. Demands for newsvendor-type products are often forecasted from censored observations. The K... In a newsvendor inventory system, demand observations often get right censored when there are lost sales and no backordering. Demands for newsvendor-type products are often forecasted from censored observations. The Kap-lan-Meier product limit estimator is the well-known nonparametric method to deal with censored data, but it is unde-fined beyond the largest observation if it is censored. To address this shortfall, some completion methods are suggested in the literature. In this paper, we propose two hypotheses to investigate estimation bias of the product limit estimator, and provide three modified completion methods based on the proposed hypotheses. The proposed hypotheses are veri-fied and the proposed completion methods are compared with current nonparametric completion methods by simulation studies. Simulation results show that biases of the proposed completion methods are significantly smaller than that of those in the literature. 展开更多
关键词 Forecasting DEMAND Censored NONPARAMETRIC Product LIMIT ESTIMATOR
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随机设计截断半参数模型中估计的渐近性 预览
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作者 陈琴 《湖州师范学院学报》 2009年第1期 16-19,共4页
考虑一类新的半参数回归模型Yi=xiβ+g(ti)+σiei,i=1,2…,n,σi^2=f(ui),其中ti为随机设计点列,Yi被随机右截断.将截断样本数据转化为完全样本数据后,用权函数和两阶段最小二乘方法得到了β,g的估计量.在适当的条件下,研... 考虑一类新的半参数回归模型Yi=xiβ+g(ti)+σiei,i=1,2…,n,σi^2=f(ui),其中ti为随机设计点列,Yi被随机右截断.将截断样本数据转化为完全样本数据后,用权函数和两阶段最小二乘方法得到了β,g的估计量.在适当的条件下,研究了参数分量β的估计的渐近正态性和非参数分量g的收敛速度,从而丰富了半参数模型的估计理论,并使其应用性更广泛. 展开更多
关键词 截断 半参数模型 渐近正态性 收敛速度
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分组与删矢数据下对数正态分布的最大似然估计 预览 被引量:2
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作者 吴其平 《福州大学学报:自然科学版》 CAS CSCD 2002年第4期422-425,共4页
讨论产品寿命服从对数正态分布, 观察数据分组与可能删矢的条件下, 最大似然估计的存在性.
关键词 删矢数据 最大似然估计 对数正态分析 分组数据 寿命试验 似然函数
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指数分布均值估计量的比较 预览
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作者 蔡明书 李树有 宓颖 《辽宁工业大学学报:自然科学版》 2019年第5期288-294,共7页
对于两个给定的指数分布总体,基于截尾样本,讨论其均值θi(i=1,2)极大似然估计的比较问题。分别就定时截尾样本和定数截尾样本,给出θi(i=1,2)极大似然估计满足随机序的充分条件。最后,针对双参数指数分布,基于逐次结尾样本,给出参数极... 对于两个给定的指数分布总体,基于截尾样本,讨论其均值θi(i=1,2)极大似然估计的比较问题。分别就定时截尾样本和定数截尾样本,给出θi(i=1,2)极大似然估计满足随机序的充分条件。最后,针对双参数指数分布,基于逐次结尾样本,给出参数极大似然估计满足随机序的充分条件,并加以证明。 展开更多
关键词 指数分布 极大似然估计(MLE) Ⅰ型截尾样本 Ⅱ型截尾样本 Ⅱ型逐次截尾样本
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Asymptotic Normality of the Nelson-Aalen and the Kaplan-Meier Estimators in Competing Risks 预览
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作者 Didier Alain Njamen Njomen 《应用数学(英文)》 2019年第7期545-560,共16页
This paper studies the asymptotic normality of the Nelson-Aalen and the Kaplan-Meier estimators in a competing risks context in presence of independent right-censorship. To prove our results, we use Robelledo’s theor... This paper studies the asymptotic normality of the Nelson-Aalen and the Kaplan-Meier estimators in a competing risks context in presence of independent right-censorship. To prove our results, we use Robelledo’s theorem which makes it possible to apply the central limit theorem to certain types of particular martingales. From the results obtained, confidence bounds for the hazard and the survival functions are provided. 展开更多
关键词 Censored Data Right-Censoring COUNTING Process Competing Risks Nelson-Aalen and Kaplan-Meier ESTIMATORS Asymptotic Properties of ESTIMATORS CONFIDENCE Bands
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对参数带约束条件的生存模型的回归分析
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作者 邓立凤 韦程东 《数学建模及其应用》 2019年第2期1-10,共10页
为了降低成本、提高研究效率,对与时间相依的数据,有偏抽样方法是广泛应用的基础抽样方法.在建模过程中,它可以从参数的先验信息中提取更有价值的信息.随着数字信息的发展,在许多领域都可以收集到协变量维数大于样本容量的高维数据.变... 为了降低成本、提高研究效率,对与时间相依的数据,有偏抽样方法是广泛应用的基础抽样方法.在建模过程中,它可以从参数的先验信息中提取更有价值的信息.随着数字信息的发展,在许多领域都可以收集到协变量维数大于样本容量的高维数据.变量选择法和独立筛选法是非常有效的降维方法.在比例风险模型中,对参数带有约束条件的回归分析,采用了修正的MM算法,但对不同的模型,此优化算法不再适用.为了克服优化问题的计算复杂难实现的困难,将蚁群算法和粒子群算法等优化算法应用到参数带约束条件的回归分析中. 展开更多
关键词 删失数据 高维协变量 带约束条件的估计 生存模型 优化算法
EM算法下飞机IDG删失数据的可靠性分析 预览
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作者 孔祥芬 张利寒 蔡峻青 《机械科学与技术》 CSCD 北大核心 2019年第7期1138-1142,共5页
为了更为精确地分析随机删失情况下故障数据的可靠性,本文以统计学理论为支撑,提出将期望-极大值(Exception maximization,EM)算法应用于随机删失数据的还原处理过程中。采集B737NG飞机IDG部件故障数据,利用K-M估计法及MATLAB软件确定... 为了更为精确地分析随机删失情况下故障数据的可靠性,本文以统计学理论为支撑,提出将期望-极大值(Exception maximization,EM)算法应用于随机删失数据的还原处理过程中。采集B737NG飞机IDG部件故障数据,利用K-M估计法及MATLAB软件确定其寿命分布类型为两参数威布尔分布;利用EM算法估计随机删失情况下威布尔分布的未知参数;进行可靠性及维修性分析。实证分析结果表明,威布尔分布下考虑删失数据时的可靠性分析精度更高,并根据该结论对B737NG飞机IDG部件维修计划的制定提出具体建议。 展开更多
关键词 随机删失 EM算法 可靠性 威布尔分布 MATLAB
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指示变量随机缺失下变系数模型的分位数回归 预览
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作者 宁黎明 何晓霞 王志明 《武汉科技大学学报》 CAS 北大核心 2019年第3期227-234,共8页
本文研究了删失数据以及删失指示量随机缺失情况下部分线性变系数模型的参数估计问题。对非参数部分采用B样条近似,对缺失的指示变量运用极大似然估计,结合分位数回归,得到了参数估计的渐近正态性质和非参数部分的收敛速度。蒙特卡洛模... 本文研究了删失数据以及删失指示量随机缺失情况下部分线性变系数模型的参数估计问题。对非参数部分采用B样条近似,对缺失的指示变量运用极大似然估计,结合分位数回归,得到了参数估计的渐近正态性质和非参数部分的收敛速度。蒙特卡洛模拟和实例分析表明,所提出的方法可以有效处理此类存在缺失的数据,获得有意义的结果。 展开更多
关键词 部分线性变系数模型 分位数回归 删失数据 删失指示量 随机缺失 B样条
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中国电影票房的影响因素研究 预览 被引量:1
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作者 华锐 王森林 许泱 《统计与决策》 CSSCI 北大核心 2019年第4期97-100,共4页
基于252部电影的数据,文章讨论口碑、关注度、宣传方式、导演、男女主角、电影档期等因素与电影票房的关系。通过实证研究发现,口碑显著地促进票房的增长,但随着票房不断增加,口碑对票房的促进作用有所降低;关注度促进电影票房的增长,... 基于252部电影的数据,文章讨论口碑、关注度、宣传方式、导演、男女主角、电影档期等因素与电影票房的关系。通过实证研究发现,口碑显著地促进票房的增长,但随着票房不断增加,口碑对票房的促进作用有所降低;关注度促进电影票房的增长,但其促进作用低于口碑;现代宣传方式对电影票房的促进作用高于传统宣传方式;明星导演和明星演员显著提高电影票房,其中,导演对票房的促进作用大于男主角,男主角对票房的促进作用大于女主角;档期显著促进电影票房的增长,档期越热门,对票房的促进作用越大。 展开更多
关键词 电影票房 影响因素 分位数回归 1%截尾
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Semiparametric quantile-difference estimation for length-biased and right-censored data
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作者 Yutao Liu Shucong Zhang Yong Zhou 《中国科学:数学英文版》 SCIE CSCD 2019年第9期1823-1838,共16页
Prevalent cohort studies frequently involve length-biased and right-censored data, a fact that has drawn considerable attention in survival analysis. In this article, we consider survival data arising from lengthbiase... Prevalent cohort studies frequently involve length-biased and right-censored data, a fact that has drawn considerable attention in survival analysis. In this article, we consider survival data arising from lengthbiased sampling, and propose a new semiparametric-model-based approach to estimate quantile differences of failure time. We establish the asymptotic properties of our new estimators theoretically under mild technical conditions, and propose a resampling method for estimating their asymptotic variance. We then conduct simulations to evaluate the empirical performance and efficiency of the proposed estimators, and demonstrate their application by a real data analysis. 展开更多
关键词 QUANTILE DIFFERENCES length-biased sampling right-censored proportional hazards model
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