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Hierarchical linear regression models for conditional quantiles

Science china Mathematics 2006年第12期49卷 1800-1815页

作者： tian maozai & chen gemai school of statistics, renmin university of china, beijing 100872, china and center for applied statistics, renmin university of china, beijing 100872, china Department of Mathematics and statistics, university of Calgary, Canada school of statistics Renmin University of China Beijing 100872 China Department of Mathematics statistics University of Calgary Canada center for applied statistics Renmin University of China Beijing 100872 China

The quantile regression has several useful features and therefore is gradually developing into a comprehensive approach to the statistical analysis of linear and nonlinear response models,but it cannot deal effectively with the data with a hierarchical *** practice,the existence of such data hierarchies is neither accidental nor ignorable,it is a common *** ignore this hierarchical data structure risks overlooking the importance of group effects,and may also render many of the traditional statistical analysis techniques used for studying data relationships *** the other hand,the hierarchical models take a hierarchical data structure into account and have also many applications in statistics,ranging from overdispersion to constructing min-max ***,the hierarchical models are virtually the mean regression,therefore,they cannot be used to characterize the entire conditional distribution of a dependent variable given high-dimensional ***,the estimated coefficient vector (marginal effects)is sensitive to an outlier observation on the dependent *** this article,a new approach,which is based on the Gauss-Seidel iteration and taking a full advantage of the quantile regression and hierarchical models,is *** the theoretical front,we also consider the asymptotic properties of the new method,obtaining the simple conditions for an n1/2-convergence and an asymptotic *** also illustrate the use of the technique with the real educational data which is hierarchical and how the results can be explained.

关键词： hierarchical quantile regression models,EQ algorithm,fixed effects,random effects,regression quantile.

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Association of Human Whole-blood NAD+Levels with Nabothian Cyst

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Biomedical and Environmental Sciences 2024年第5期37卷 471-478页

作者： XU Ling WANG Yue Xuan WANG Wei FAN Xue chen Xue Yu ZHOU tian Yun LIU Yu He YU Ye YANG Fan JU Zhen Yu ZHOU Yong WANG Deng Liang Clinical Research Institute Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China NHC Key Lab of Reproduction Regulation Shanghai Engineering Research Center of Reproductive Health Drugs and DevicesShanghai Institute for Biomedical and Pharmaceutical TechnologiesShanghai 200237China Department of applied statistics Johannes Kepler University LinzLinz 4040Austria Hematology center Beijing Key Laboratory of Pediatric Hematology OncologyNational Key Discipline of Pediatrics(Capital Medical University)Key Laboratory of Major Diseases in ChildrenMinistry of EducationBeijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China Department of Biostatistics School of Public HealthCheeloo College of MedicineShandong UniversityJinan 250012ShandongChina Clinical Medicine School of Basic MedicineShanghai Medical College Fudan UniversityShanghai 200032China Department of Biochemistry and Molecular Biology Hengyang Medical SchoolUniversity of South ChinaHengyang 421001HunanChina Administrative Office Total Quality Management OfficeTotal Quality Management InstituteShanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China The First Affiliated Hospital of Jinan university Institute of Aging and Regenerative MedicineJinan UniversityJinan 510632GuangzhouChina Department of Scientific Research The First Affiliated Hospital of Huzhou UniversityHuzhou 313000ZhejiangChina Department of Neurosurgery Neurosurgery Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhou 350005FujianChina Department of Neurosurgery Binhai Branch of National Regional Medical CenterThe First Affiliated HospitalFujian Medical UniversityFuzhou 350209FujianChina Fujian Provincial Institutes of Brain Disorders and Brain Sciences The First Affiliated HospitalFujian Medical UniversityFuzhou 350005FujianChina Fujian Provincial Clinical Research center for Neurological

Objective Little is known about the association between whole-blood nicotinamide adenine dinucleotide(NAD^(+))levels and nabothian *** study aimed to assess the association between NAD^(+)levels and nabothian cysts in healthy Chinese *** Multivariate logistic regression analysis was performed to analyze the association between NAD^(+)levels and nabothian *** The mean age was 43.0±11.5 years,and the mean level of NAD^(+)was 31.3±5.3μmol/*** cysts occurred in 184(27.7%)participants,with single and multiple cysts in 100(15.0%)and84(12.6%)participants,*** total nabothian cyst prevalence gradually decreased from37.4%to 21.6%from Q1 to Q4 of NAD^(+)and the prevalence of single and multiple nabothian cysts also decreased across the NAD^(+)*** compared with the highest NAD^(+)quartile(≥34.4μmol/L),the adjusted odds ratios with 95%confidence interval of the NAD^(+)Q1 was 1.89(1.14–3.14)for total nabothian *** risk of total and single nabothian cysts linearly decreased with increasing NAD^(+)levels,while the risk of multiple nabothian cysts decreased more rapidly at NAD^(+)levels of 28.0 to35.0μmol/***:Low NAD^(+)levels were associated with an increased risk of total and multiple nabothian cysts.

关键词： Nicotinamide adenine dinucleotide Nabothian cyst Female Risk factor

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Parameters estimation and application of generalized exponential distribution under grouped and right-censored data

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Frontiers of Mathematics in china 2023年第3期18卷 165-174页

作者： Yuzhu tian maozai tian Ping chen center for applied statistics Renmin University of ChinaBeijing 100872China school of Mathematics and statistics Tianshui Normal UniversityTianshui 741001China Dependment of Mathematics Southeast UniversityNanjing 210096China

Generalized exponential distribution is a class of important distribution in lifedata analysis,especially in some skewed *** Parameter estimation problem for generalized exponential distribution model with grouped and right-censored data is *** maximum likelihood estimators are obtained using the EM *** simulations are carried out to illustrate that the proposed algorithm is effective for the ***,a set of medicine data is analyzed by generalized exponential distribution.

关键词： Generalized exponential distribution grouped and right-censored data EM algorithm

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河南省商城县2种动物发热伴血小板减少综合征病毒感染情况的调查研究

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中华疾病控制杂志 2024年第1期28卷 83-91页

作者：刘万双陈浩荣代科蒋宝贵陈津津田珅吴家红刘玮方立群贵州医科大学公共卫生学院流行病与卫生统计学系贵阳550025 北京化工大学生命科学与技术学院制药工程学系北京100029 军事医学研究院微生物流行病研究所病原微生物生物安全国家重点实验室北京100071 广州医科大学公共卫生学院流行病与卫生统计学系广州511436

目的通过开展发热伴血小板减少综合征(severe fever with thrombocytopenia syndrome,SFTS)自然疫源地动物宿主感染新布尼亚病毒(severe fever with thrombocytopenia syndrome virus,SFTSV)的调查研究,明确SFTS自然疫源地SFTSV的传播风险与影响因素,为SFTS的针对性防控提供科学依据。方法采用卫星定位技术连续跟踪商城县邱湾村、平塘村和龙头桥村3个村庄部分村民家养狗日常活动轨迹2周并采集血清样本,使用间接荧光抗体试验(indirect immunofluorescence assay,IFA)法检测家养狗血清SFTSV⁃IgG抗体,使用logistic回归分析模型分析影响家养狗感染SFTSV的潜在环境影响因素;采用夹(笼)夜法和粘鼠板法对家养狗活动区域内的啮齿动物及小型哺乳动物种群进行密度调查,针对保守基因进行PCR种类鉴定,并采用荧光PCR和酶联免疫吸附试验(enzyme linked immunosorbent assay,ELISA)方法检测啮齿动物及小型哺乳动物SFTSV感染情况。结果通过卫星定位共追踪26条家养狗的日常活动范围信息,采集37条家养狗52份血清,SFTSV⁃IgG抗体总阳性率为59.46%;共捕获啮齿动物及小型哺乳动物419只,优势种为黄胸鼠、小家鼠、黑线姬鼠,未有SFTSV阳性标本检出;家养狗活动中心离主干道路距离远和到过林地的频次多是感染SFTSV的危险因素,家养狗活动中心离林地距离远是感染SFTSV的保护因素。结论商城县家养狗SFTSV抗体阳性率较高,感染SFTSV与生态环境相关,建议进一步扩大家养动物的种类,开展SFTSV感染情况的研究;啮齿动物的SFTSV感染率低,在SFTSV自然循环过程中的作用需进一步调查。

关键词：新布尼亚病毒蜱传疾病啮齿动物血清学危险因素血小板减少综合征发热

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Composite Hierachical Linear Quantile Regression

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Acta Mathematicae Applicatae Sinica 2014年第1期30卷 49-64页

作者： Yan-liang chen Mao-zai tian Ke-ming YU Jian-xin PAN center for applied statistics School of StatisticsRenmin University of China school of Business Shihezi University Mathematical Sciences John Crank 209Brunel University school of Mathematics The University of Manchester school of statistics and Mathematics Yunnan University of Finance and Economics

Multilevel （hierarchical） modeling is a generalization of linear and generalized linear modeling in which regression coefficients are modeled through a model, whose parameters are also estimated from data. Multilevel model fails to fit well typically by the use of the EM algorithm once one of level error variance （like Cauchy distribution） tends to infinity. This paper proposes a composite multilevel to combine the nested structure of multilevel data and the robustness of the composite quantile regression, which greatly improves the efficiency and precision of the estimation. The new approach, which is based on the Gauss-Seidel iteration and takes a full advantage of the composite quantile regression and multilevel models, still works well when the error variance tends to infinity, We show that even the error distribution is normal, the MSE of the estimation of composite multilevel quantile regression models nearly equals to mean regression. When the error distribution is not normal, our method still enjoys great advantages in terms of estimation efficiency.

关键词： multilevel model composite quantile regression E-CQ algorithm, fixed effects, random effects

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空间变系数分层自相关模型的截面似然估计及应用

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应用数学学报 2023年第2期46卷 166-195页

作者：孟丽君戴晓文古丽斯坦·库尔班尼牙孜陈小昆田茂再新疆财经大学统计与数据科学学院乌鲁木齐830012 上海立信会计金融学院统计与数学学院上海立信会计金融学院交叉数据研究院上海201209 中国人民大学统计学院北京100872

非参数空间动态模型作为一类能同时处理回归分析中的空间非平稳性和空间依赖性现象的建模技术,在多类问题的研究中得到了广泛的应用.本篇将重点讨论当因变量中存在分层结构情形时的空间变系数模型.通过截面极大似然方法给出模型估计,并... 详细信息

非参数空间动态模型作为一类能同时处理回归分析中的空间非平稳性和空间依赖性现象的建模技术,在多类问题的研究中得到了广泛的应用.本篇将重点讨论当因变量中存在分层结构情形时的空间变系数模型.通过截面极大似然方法给出模型估计,并通过AIC准则将模型参数和非参数分量加以识别.证明了估计量的一致性和渐近正态性,蒙特卡洛数值模拟表明:在有限样本时该模型及方法是有效的.在对我国地方经济社会发展集聚性与差异的应用研究中,省内城市之间的经济发展空间溢出效应大于省边界城市之间的溢出效应,这两种空间溢出效应都是不可忽视的;此外,对外贸易和城镇化率对经济发展的影响不随着空间位置而发生变化,而其他影响因素,包括:人口密度、人力资本、储蓄水平、产业结构、政府干预、社会需求和公路密度对经济发展的影响存在显著的空间异质性.

关键词：空间分层空间集聚空间变系数分层自相关模型截面极大似然估计

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供需两侧视角下煤炭产业国家价值链嵌入与产业关联问题研究——蒙、晋、陕三省(自治区)的数据分析

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数理统计与管理 2021年第2期40卷 222-232页

作者：韩丽萍高甜甜张茜陈玉宏刘俊华内蒙古工业大学经济管理学院内蒙古呼和浩特010051 内蒙古互联网经济研究中心内蒙古呼和浩特010051 内蒙古现代物流与供应链管理研究中心内蒙古呼和浩特010051

本文在构建上、下游度指数模型测算蒙、晋、陕煤炭产业不同时点嵌入国家价值链位置的基础上,从产业关联视角分析煤炭产业作为供需双方的中间产品的流向和来源,并对煤炭产业嵌入国家价值链位置变动的原因作出了合理解释.得到如下结论:(1)... 详细信息

本文在构建上、下游度指数模型测算蒙、晋、陕煤炭产业不同时点嵌入国家价值链位置的基础上,从产业关联视角分析煤炭产业作为供需双方的中间产品的流向和来源,并对煤炭产业嵌入国家价值链位置变动的原因作出了合理解释.得到如下结论:(1)2002-2012年间,蒙、晋、陕煤炭产业在产出供给链的总体分布格局为蒙>陕>晋;在投入需求链的分布格局为蒙>晋>陕,但内蒙古煤炭产业在国家价值链的位置整体下降,晋陕两省煤炭产业在产出供给链的位置下降,在投入需求链的位置上升.(2)在产出供给链上,三省煤炭产业的产出主要用于电力、热力的生产和供应业、石油加工、炼焦及核燃料加工业以及煤炭开采和洗选业;在投入需求链上,三省煤炭产业的需求主要来源于交通运输、仓储、煤炭开采及洗选业;(3)产业结构变动及产业关联效应是三省煤炭产业嵌入位置变动的主要原因.

关键词：煤炭产业国家价值链位置产业关联结构变动

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湍流边界层内不同粒径颗粒行为的PIV实验研究

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化学工程 2018年第12期46卷 59-63页

作者：孙姣轩瑞祥高天达陈文义河北工业大学过程装备与控制工程系天津300130 河北工业大学工程流动与过程强化研究中心天津300130 河北工业大学天津大学机械工程学院力学系天津300350

为探究不同粒径颗粒在湍流边界层中的运动规律,采用粒子图像测速技术(PIV)对颗粒在平板湍流边界层内运动行为进行研究,分析同一来流速度条件下速度剖面、湍流度、雷诺应力统计量。运用新象限分裂法和空间相位平均法提取"喷射"和"扫掠"... 详细信息

为探究不同粒径颗粒在湍流边界层中的运动规律,采用粒子图像测速技术(PIV)对颗粒在平板湍流边界层内运动行为进行研究,分析同一来流速度条件下速度剖面、湍流度、雷诺应力统计量。运用新象限分裂法和空间相位平均法提取"喷射"和"扫掠"事件的脉动速度、雷诺应力二维空间拓扑形态。发现:颗粒速度剖面无太大差别,大颗粒湍流度和雷诺应力比小颗粒大,颗粒流向湍流度均大于法向湍流度;大颗粒脉动速度及喷射数目大于小颗粒,小颗粒喷射数目小于扫掠事件,说明大颗粒与周围流体动量交换更强烈,能量输运更强,在化工生产及污水处理方面更具前景。

关键词：湍流边界层 PIV 颗粒相干结构空间相位平均

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基于区块链的物联网节点位置隐私保护模型

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应用科学学报 2020年第1期38卷 139-151页

作者：佘维陈建森顾志豪田钊徐力刘炜郑州大学软件学院郑州450001 郑州大学互联网医疗与健康服务河南省协同创新中心郑州450001

物联网正在改变消费者的行为和业务流程.针对物联网设备的信息隐私及安全问题,提出基于区块链技术的物联网设备位置信息保护模型.该模型首先借助区块链技术将记录设备标识,保证物联网设备信息不可篡改;然后基于白名单技术实现分布式哈... 详细信息

物联网正在改变消费者的行为和业务流程.针对物联网设备的信息隐私及安全问题,提出基于区块链技术的物联网设备位置信息保护模型.该模型首先借助区块链技术将记录设备标识,保证物联网设备信息不可篡改;然后基于白名单技术实现分布式哈希表网络,并对设备位置信息进行异或处理以隐藏物联网的网络拓扑,保护物联网设备的位置信息;最后根据k-匿名算法泛化数据的敏感属性为用户提供区域信息统计服务.实验结果证明该模型可以有效隐藏设备位置信息,同时能够提供定制的区域统计服务并且保护用户信息安全.

关键词：物联网位置信息保护区块链分布式哈希表 k-匿名

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Sex differences in the scored Patient-Generated Subjective Global Assessment in 19,528 cancer patients

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Journal of Nutritional Oncology 2023年第1期8卷 38-46页

作者： Wang Yan-Li Wu tian-tian Fu Zhen-Ming Guo Zeng-Qing Lin Yuan Shi Ying-Ying Hu Wen Ba Yi Li Su-Yi Li Zeng-Ning Wang Kun-Hua Wu Jing He Ying Yang Jia-Jun Xie Cong-Hua Zhou Fu-Xiang Song Xin-Xia chen Gong-Yan Ma Wen-Jun Luo Su-Xia chen Zi-Hua Cong Ming-Hua Ma Hu Zhou Chun-Ling Wang Wei Luo Qi Shi Yong-Mei Qi Yu-Mei Jiang Hai-Ping Guan Wen-Xian chen Jun-Qiang chen Jia-Xin Fang Yu Zhou Lan Feng Yong-Dong Tan Rong-Shao Li Tao Ou Jun-Wen Zhao Qing-Chuan Wu Jian-Xiong Lin Xin Yang Liu-Qing Zhang Qi Jia Ping-Ping Li Wei Xu Hong-Xia Shi Han-Ping Song Chun-Hua The Investigation on Nutrition Status and Clinical Outcome of Common Cancers(INSCOC)Group Chinese Society of Nutritional Oncology Department of Epidemiology and statistics College of Public HealthZhengzhou UniversityZhengzhouHenanChina Cancer center Renmin Hospital of Wuhan UniversityWuhanHubeiChina Department of Medical Oncology Fujian Cancer HospitalFujian Medical University Cancer HospitalFuzhouFujianChina Department of Gastrointestinal Surgery Affiliated Tumor Hospital of Guangxi Medical UniversityNanningGuangxiChina Department of Surgery The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina Department of Clinical Nutrition West China Hospital of Sichuan UniversityChengduSichuanChina Department of Gastrointestinal Oncology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin Key Laboratory of Cancer Prevention and TherapyTianjinChina Department of Nutrition and Metabolism of Oncology Affiliated Provincial Hospital of Anhui Medical UniversityHefeiAnhuiChina Department of Clinical Nutrition The First Hospital of Hebei Medical UniversityShijiazhuangHebeiChina Department of Gastrointestinal Surgery Institute of GastroenterologyThe First Affiliated Hospital of Kunming Medical UniversityKunmingYunnanChina Zhongshan chenxinghai Hospital(Affiliated Zhongshan chenxinghai Hospital of Guangdong Medical university) ZhongshanGuangdongChina Department of Clinical Nutrition The First People's Hospital of KashiKashiXinjiangChina Department of Clinical Nutrition Chongqing General HospitalChongqingChina Department of Colorectal and Anal Surgery Huizhou Municipal Central HospitalHuizhouGuangdongChina Department of Radiation and Medical Oncology Zhongnan Hospital of Wuhan UniversityWuhanHubeiChina Department of Oncology Xingtai People’s HospitalHebei Medical UniversityXingtaiHebeiChina The First Department of the Tumor Hospital of Harbin Medical university HarbinHeilongjiangChina Department of Nutrition Guangdong General HospitalGuangdong Academy of Medical SciencesGuangzhouGuangdongChina Department of Oncology Affiliated

Background:The scored Patient-Generated Subjective Global Assessment(PG-SGA)has been widely used to assess the nutritional status of cancer *** purpose of this study is to compare the differences in PG-SGA scores and the 7 domain scores of the PG-SGA in male and female cancer ***:This study was conducted at 72 hospitals from July 2013 to December 2018,a part of the Investigation on Nutritional Status and its Clinical Outcomes of Common *** PG-SGA was recorded to evaluate the nutritional status of patients.A total of 19,528 patients with 13 common malignancies were included in this *** t test and the χ^(2) test were applied to analyze the sex diferences in the 7 domain *** Cancer Genome Atlas(TCGA)database was used to analyze the expression levels of symptom-related ***:There were significant sex dfferences in the PG-SGA(P=0.032),notably in patients with gastric cancer(male vs female:9.09±4.86 vs 9.58±5.07,P=0.005)and esophageal cancer(9.64±4.90 vs 10.46±4.96,P=0.011)and the average total PG-SGA of female patients was slightly higher than that of male patients(7.64±4.98 vs 7.77±5.14).The differences were mainly related to the weight,eating,symptom,as well as activity and physical function scores in the stratified *** causes of the sex differences were the rates of nausea,vomiting,dry mouth,and other symptoms,in both gastric and esophageal cancer *** of the TCGA database suggested that most of the related genes were sex neutral,except for genes related to dysphagia in gastric cancer(VEGFC was higher in female patients,VEGFA and VEGFB higher in male patients).Conclusions:There are sex differences in the PG-SGA scores in patients with various tumor types(female patients generally had higher scores than male patients),with differences mainly in the weight,eating,symptom,as well as activity and physical function *** sex differences in PG-SGA scores might be due to the differences i

关键词： PG-SGA Sex differences Malnutrition Cancer patients TCGA database

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