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Open Journal of Epidemiology 2016年第3期6卷 167-172页

作者： Shafquat Rozi Sadia Mahmud Gillian Lancaster Nida Zahid Department of Mathematics and Statistics Lancaster University Lancashire UK Department of Community Health Sciences Aga Khan University Karachi Pakistan Department of Paediatrics & Child Health Aga Khan University Karachi Pakistan

Introduction: Among young teens, about one in five smokes worldwide. Adolescents spend a considerable amount of their time in school, and the school environment is therefore important for child health practices and outcomes. Objectives: We aimed to investigate the impact on smoking behavior of the school environment and the personal characteristics of male teenage students attending schools in Pakistan, taking into account the survey sampling structure. Methods: A two-stage cluster sampling with stratification was employed, and we interviewed 772 male secondary school students. We adopted random effect and generalizing estimating equation models. Results: Peer pressure in particular had a strong influence on adolescents smoking;those whose friends smoked were up to 6 times more likely to smoke. Family smoking was also significantly associated with adolescents smoking, but those students whose mother was educated were 50% less likely to smoke. The fitted random effect model indicated that the between school variability was significant (p-value model showed that variability among schools was not significantly different for public and private schools. Conclusion: Public health campaigns for smoking cessation should target not only the individual but also the families of adolescents attending schools.

关键词： Teenage Smoking multilevel model Binary Outcome Public & Private Schools

Modification of laser-induced state in atomic attosecond transient absorption by the XUV pulse pair

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Communications in Theoretical Physics 2023年第1期75卷 138-146页

作者： Xuhong Li Guanglu Yuan Xiangyu Tang Yong Fu Kan Wang Bincheng Wang Cheng Jin Department of Applied Physics Nanjing University of Science and TechnologyNanjing 210094China Experimental teaching center of physics Nanjing University of Science and TechnologyNanjing 210094China MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing Nanjing University of Science and TechnologyNanjing 210094China

Attosecond transient absorption(ATA)has been developed as an all-optical technique for probing electron dynamics in *** we present a scheme that can modify the laserinduced state and the corresponding ATA spectrum via excitation by a pair of XUV attosecond pulses and by a time-delayed mid-infrared(MIR)laser *** from the scheme of the electronic excitation by a single XUV attosecond pulse,the application of a pair of XUV pulses provides extra degrees of freedom,such as the time delay and the intensity ratio between two XUV pulses,which make it possible to adjust the pump process,resulting in the modification of the ATA *** show that by varying the time delay between the two XUV pulses,the population of the dark state and the ATA spectrum of the laser-induced state have periodic *** also demonstrate that the peak of the ATA spectrum of the laser-induced state appears at a fixed time delay between the XUV pair and the MIR laser when the intensity ratio is large,and it changes with the time delay when the intensity ratio is small,which can be related to either one of two peaks in the population of the dark state.

关键词： attosecond transient absorption laser-induced state XUV pulse pair dark state multilevel model

Numerical Simulation of Tidal Current in a Bay

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China Ocean Engineering 2000年第1期15卷 121-128页

作者：曾一非 Coll. of Nav. Arch. and Ocean Eng. Shanghai Jiaotong University Shanghai 200030 China Faculty of Engineering University of Tokyo Bunkyo-ku Tokyo 113 7-3-1 Hongo Japan

Based on the multilevel model, numerical calculations of tidal current affected by the M-2 tide in the Tokyo Bay have been carried out. The results of calculation are compared with the data observed in the Tokyo Bay and the result calculated by an approximate formula as the Tokyo Bay is regarded as a rectangular bay, and good agreement is found. It is proved that the mathematical model and the calculation method are correct and useable.

关键词： multilevel model Navier-Stokes equations M-2 tide numerical calculation

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

The association between drinking water salinity and hypertension in coastal Bangladesh

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Global Health Journal 2020年第4期4卷 153-158页

作者： Jahidur Rahman Khan Nabil Awan Rownak Jahan Archiee Nasrin Sultana Olav Muurlink Health Research Institute Faculty of HealthUniversity of CanberraAustralia Biomedical Research Foundation(BRF) DhakaBangladesh Institute of Statistical Research and Training University of DhakaDhakaBangladesh. Department of Biostatistics University of PittsburghPittsburghU.S.A. Karolinska Institutet StockholmSweden Department of Statistics Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipurBangladesh School of Business and Law Central Queensland UniversityBrisbaneAustralia

Aims:This study aims to explore the association between drinking water salinity and hypertension in three coastal sub-districts of ***:The study uses complete data on 6,296 individuals extracted from the latest Bangladesh Poverty and Groundwater Salinity Survey and a mixed-effects logistic regression model as the analytical ***:Mixed-effects logistic regression analysis shows a significant association of medium or higherlevel salinity with hypertension(adjusted odds ratio[AOR]1.650,95%confidence interval[CI]:1.101—2.473).Other variables significantly associated with hypertension are age,sex,education status,water source,and geographical location.A sizable proportion of the total individual-level variance in the probability of being hypertensive was at household-level(20%)and cluster-level(8%).Conclusion:The findings from this study suggest that greater salinity in potable water common in coastal areas in Bangladesh is associated with increased risk of *** study refrains from asserting causality but seeks to stimulate public health and policy interventions to address the increased risk.

关键词： Salinity Hypertension multilevel model Bangladesh

Vertical Specialization and Trade Growth in Northeast Asia

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China & World Economy 2011年第2期19卷 109-126页

作者： Yun Seop Hwang Jun Song Soo Eun Kim Associate Professor Department of International Business and Trade Kyung Hee University Seoul Korea. Email: rusiahys@khu.ac.kr China Citic Bank Cheng Du Yinhe Dynasty Sub-Branch Works Ministry Chengdu China. Email: ck_sjun@*** Doctoral candidate Graduate School of International Business and Trade Kyung Hee University Seoul Korea. Email: sookim@khu.ac.kr. *Correspondence: Doctoral candidate Graduate School of International Business and Trade Kyung Hee University Seoul Korea. Email: sookim@khu.ac.kr.

As the global economy has become further integrated, the international production chain has become more sophisticated, with diversified stages of production located in different countries. Economic theorists have argued that the fragmentation of the global production chain is partly attributable to the high growth in international trade over the past several decades. In this study, we examine vertical specialization in China, Japan and Korea, and its contribution to these nations＇ trade. Using a multilevel model, it is illustrated that vertical specialization has encouraged increases in trade among all three countries. In particular, China ＇s outcome is remarkable considering how recently it became a member of the WTO.

关键词： fragmentation of global production multilevel model trade growth vertical specialization

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关于多水平删失正态回归模型的模拟研究

地区教育人力资本与教育代际传递：抑制或促进

统计与精算 2009年第4期 117-120,127页

作者：郝永红张志琴王彤

目的探讨不同条件下的数据对于多水平删失正态回归模型参数点估计及其标准误的影响。方法模拟二水平删失正态回归数据，分别拟合二水平正态回归模型和二水平删失正态回归模型，并给出不同的一、二水平样本量及内相关系数条件，比较... 详细信息

目的探讨不同条件下的数据对于多水平删失正态回归模型参数点估计及其标准误的影响。方法模拟二水平删失正态回归数据，分别拟合二水平正态回归模型和二水平删失正态回归模型，并给出不同的一、二水平样本量及内相关系数条件，比较其参数点估计及参数标准误估计结果。结果二水平样本量越大，固定系数、一水平残差及残差间协方差的标准误估计越准确，而方差成分标准误估计的准确性对于一水平样本量要求较弱，内相关系数对参数标准误估计的准确性影响不大。结论存在删失因变量的多水平结构数据应使用多水平删失正态回归模型进行参数估计，其标准误与合适的各水平样本含量及内相关系数有关。

关键词：多水平模型删失回归模型多水平删失正态回归模型模拟研究 multilevel model Censored regression model multilevel censored normal regression model Simulation study

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