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Adaptive Random Effects/Coefficients Modeling
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作者 George J. Knafl 《Open Journal of Statistics》 2024年第2期179-206,共28页
Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using general... Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using generalized linear models in fixed effects/coefficients. Correlations are modeled using random effects/coefficients. Nonlinearity is addressed using power transforms of primary (untransformed) predictors. Parameter estimation is based on extended linear mixed modeling generalizing both generalized estimating equations and linear mixed modeling. Models are evaluated using likelihood cross-validation (LCV) scores and are generated adaptively using a heuristic search controlled by LCV scores. Cases covered include linear, Poisson, logistic, exponential, and discrete regression of correlated continuous, count/rate, dichotomous, positive continuous, and discrete numeric outcomes treated as normally, Poisson, Bernoulli, exponentially, and discrete numerically distributed, respectively. Example analyses are also generated for these five cases to compare adaptive random effects/coefficients modeling of correlated outcomes to previously developed adaptive modeling based on directly specified covariance structures. Adaptive random effects/coefficients modeling substantially outperforms direct covariance modeling in the linear, exponential, and discrete regression example analyses. It generates equivalent results in the logistic regression example analyses and it is substantially outperformed in the Poisson regression case. Random effects/coefficients modeling of correlated outcomes can provide substantial improvements in model selection compared to directly specified covariance modeling. However, directly specified covariance modeling can generate competitive or substantially better results in some cases while usually requiring less computation time. 展开更多
关键词 Adaptive Regression Correlated Outcomes Extended Linear Mixed Modeling Fractional Polynomials Likelihood Cross-Validation random effects/Coefficients
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Different effects of 24 dietary intakes on gastroesophageal reflux disease: A mendelian randomization
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作者 Yu-Xin Liu Wen-Tao Yang Yang Li 《World Journal of Clinical Cases》 SCIE 2024年第14期2370-2381,共12页
BACKGROUND In observational studies,dietary intakes are associated with gastroesophageal re-flux disease(GERD).AIM To conduct a two-sample mendelian randomization(MR)analysis to determine whether those associations ar... BACKGROUND In observational studies,dietary intakes are associated with gastroesophageal re-flux disease(GERD).AIM To conduct a two-sample mendelian randomization(MR)analysis to determine whether those associations are causal.METHODS To explore the relationship between dietary intake and the risk of GERD,we extracted appropriate single nucleotide polymorphisms from genome-wide asso-ciation study data on 24 dietary intakes.Three methods were adopted for data analysis:Inverse variance weighting,weighted median methods,and MR-Egger's method.The odds ratio(OR)and 95%confidence interval(CI)were used to eva-luate the causal association between dietary intake and GERD.RESULTS Our univariate Mendelian randomization(UVMR)results showed significant evidence that pork intake(OR,2.83;95%CI:1.76-4.55;P=1.84×10–5),beer intake(OR,2.70,95%CI:2.00-3.64;P=6.54×10–11),non-oily fish intake(OR,2.41;95%CI:1.49-3.91;P=3.59×10–4)have a protective effect on GERD.In addition,dried fruit intake(OR,0.37;95%CI:0.27-0.50;6.27×10–11),red wine intake(OR,0.34;95%CI:0.25-0.47;P=1.90×10-11),cheese intake(OR,0.46;95%CI:0.39-0.55;P=3.73×10-19),bread intake(OR,0.72;95%CI:0.56-0.92;P=0.0009)and cereal intake(OR,0.45;95%CI:0.36-0.57;P=2.07×10-11)were negatively associated with the risk of GERD.There was a suggestive asso-ciation for genetically predicted coffee intake(OR per one SD increase,1.22,95%CI:1.03-1.44;P=0.019).Multi-variate Mendelian randomization further confirmed that dried fruit intake,red wine intake,cheese intake,and cereal intake directly affected GERD.In contrast,the impact of pork intake,beer intake,non-oily fish intake,and bread intake on GERD was partly driven by the common risk factors for GERD.However,after adjusting for all four elements,there was no longer a suggestive association between coffee intake and GERD.CONCLUSION This study provides MR evidence to support the causal relationship between a broad range of dietary intake and GERD,providing new insights for the treatment and prevention of GERD. 展开更多
关键词 DIETARY Gastroesophageal reflux disease Mendelian randomization Disease management randomized controlled trial
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Effect of Jianpi Shengxue Tablet on Iron Metabolism and Nutritional Status in Patients with Renal Anemia:A Prospective,Randomized,Open,Parallel Controlled and Multicenter Clinical Study
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作者 Juan YANG Meng-yuan LIANG +15 位作者 Yu LI Hao ZHANG Wei LI Jing LV Li-ping DONG Jing-song JIN Cheng YANG Qing-hong ZHANG Li LONG Rong ZOU Yi GAO Dan SONG Chun-qin PAN Ying YAO Xiao-lin ZHAN Xiao-hui WANG 《Current Medical Science》 SCIE CAS 2024年第3期603-610,共8页
Objective This study aimed to analyze the clinical efficacy of the Jianpi Shengxue tablet for treating renal anemia.Methods A total of 200 patients with renal anemia from December 2020 to December 2022 were enrolled a... Objective This study aimed to analyze the clinical efficacy of the Jianpi Shengxue tablet for treating renal anemia.Methods A total of 200 patients with renal anemia from December 2020 to December 2022 were enrolled and randomly divided into two groups.Patients in the control group were treated with polysaccharide-iron complex,and those in the experimental group were administered Jianpi Shengxue tablet.After 8 weeks of continuous treatment,the therapeutic outcomes regarding anemia were compared between the two groups.Results After treatment,the red blood cell(RBC)count,hematocrit(HCT),reticulocyte percentage(RET),ferritin(SF),serum iron(SI),transferrin saturation(TSAT),and serum albumin(ALB)all increased(P<0.01),and the clinical symptom score and total iron binding capacity decreased(P<0.01)in the experimental group.Moreover,the improvements in RBC,HCT,RET,SF,SI,TAST,ALB,and clinical symptoms(fatigue,anorexia,dull skin complexion,numbness of hands and feet)in the experimental group were significantly greater than those in the control group(P<0.05).The total effective rate for treating renal anemia was significantly higher in the experimental group than in the control group(P<0.01).Conclusion The Jianpi Shengxue tablet demonstrates efficacy in treating renal anemia,leading to significant improvements in the laboratory examination results and clinical symptoms of patients with renal anemia. 展开更多
关键词 Jianpi Shengxue tablet renal anemia randomIZED OPEN parallel control multicenter clinical study
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Modifiable factors mediating the effects of educational attainment on gestational diabetes mellitus: A two-step Mendelian randomization study
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作者 Ming-Yue Ma Ya-Song Zhao 《World Journal of Clinical Cases》 SCIE 2024年第26期5937-5945,共9页
BACKGROUND Although there is currently a wealth of evidence to indicate that maternal educational attainment is associated with gestational diabetes mellitus(GDM),the specific modifiable risk factors that mediate the ... BACKGROUND Although there is currently a wealth of evidence to indicate that maternal educational attainment is associated with gestational diabetes mellitus(GDM),the specific modifiable risk factors that mediate the causal relationship between these two variables have yet to be identified.AIM To identify the specific modifiable risk factors that mediate the causal relationship between the level of maternal education and GDM.METHODS Mendelian randomization(MR)was conducted using data from genome-wide association studies of European populations.We initially performed a two-sample MR analysis using data on genetic variants associated with the duration of education as instruments,and subsequently adopted a two-step MR approach using metabolic and lifestyle factors as mediators to examine the mechanisms underlying the relationship between the level of maternal education and risk of developing GDM.In addition,we calculated the proportions of total causal effects mediated by identified metabolic and lifestyle factors.RESULTS A genetically predicted higher educational attainment was found to be associated with a lower risk of developing GDM(OR:0.71,95%CI:0.60-0.84).Among the metabolic factors assessed,four emerged as potential mediators of the education-GDM association,which,ranked by mediated proportions,were as follows:Waist-to-hip-ratio(31.56%,95%CI:12.38%-50.70%),body mass index(19.20%,95%CI:12.03%-26.42%),high-density lipoprotein cholesterol(12.81%,95%CI:8.65%-17.05%),and apolipoprotein A-1(7.70%,95%CI:4.32%-11.05%).These findings proved to be robust to sensitivity analyses.CONCLUSION Our findings indicate a causal relationship between lower levels of maternal education and the risk of developing GDM can be partly explained by adverse metabolic profiles. 展开更多
关键词 Educational status Gestational diabetes mellitus METABOLISM Lifestyle factors Mendelian randomization analysis
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Association of education with cholelithiasis and mediating effects of cardiometabolic factors:A Mendelian randomization study
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作者 Chang-Lei Li Yu-Kun Liu +1 位作者 Ying-Ying Lan Zu-Sen Wang 《World Journal of Clinical Cases》 SCIE 2024年第20期4272-4288,共17页
BACKGROUND Education,cognition,and intelligence are associated with cholelithiasis occurrence,yet which one has a prominent effect on cholelithiasis and which cardiometabolic risk factors mediate the causal relationsh... BACKGROUND Education,cognition,and intelligence are associated with cholelithiasis occurrence,yet which one has a prominent effect on cholelithiasis and which cardiometabolic risk factors mediate the causal relationship remain unelucidated.AIM To explore the causal associations between education,cognition,and intelligence and cholelithiasis,and the cardiometabolic risk factors that mediate the associations.METHODS Applying genome-wide association study summary statistics of primarily European individuals,we utilized two-sample multivariable Mendelian randomization to estimate the independent effects of education,intelligence,and cognition on cholelithiasis and cholecystitis(FinnGen study,37041 and 11632 patients,respectively;n=486484 participants)and performed two-step Mendelian randomization to evaluate 21 potential mediators and their mediating effects on the relationships between each exposure and cholelithiasis.RESULTS Inverse variance weighted Mendelian randomization results from the FinnGen consortium showed that genetically higher education,cognition,or intelligence were not independently associated with cholelithiasis and cholecystitis;when adjusted for cholelithiasis,higher education still presented an inverse effect on cholecystitis[odds ratio:0.292(95%CI:0.171-0.501)],which could not be induced by cognition or intelligence.Five out of 21 cardiometabolic risk factors were perceived as mediators of the association between education and cholelithiasis,including body mass index(20.84%),body fat percentage(40.3%),waist circumference(44.4%),waist-to-hip ratio(32.9%),and time spent watching television(41.6%),while time spent watching television was also a mediator from cognition(20.4%)and intelligence to cholelithiasis(28.4%).All results were robust to sensitivity analyses.CONCLUSION Education,cognition,and intelligence all play crucial roles in the development of cholelithiasis,and several cardiometabolic mediators have been identified for prevention of cholelithiasis due to defects in each exposure. 展开更多
关键词 CHOLELITHIASIS Mendelian randomization Mediation analysis Education attainment Cardiometabolic risk factors COGNITION INTELLIGENCE
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Effects of Lycium barbarum polysaccharide on cytokines in adolescents with subthreshold depression:a randomized controlled study
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作者 Xiaoyue Li Tao Liu +6 位作者 Xuan Mo Runhua Wang Xueyan Kong Robin Shao Roger S.Mclntyre Kwok-Fai So Kangguang Lin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期2036-2040,共5页
Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses.Moreover,anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms.Lyci... Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses.Moreover,anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms.Lycium barbarum polysaccharide(LBP),derived from Goji berries,exhibits notable antioxidative and anti-inflammatory properties.In our recent double-blinded randomized placebo-controlled trial,we found that LBP significantly reduced depressive symptoms in adolescents with subthreshold depression.It is presumed that the antidepressant effect of LBP may be associated with its influence on inflammatory cytokines.In the double-blinded randomized controlled trial,we enrolled 29 adolescents with subthreshold depression and randomly divided them into an LBP group and a placebo group.In the LBP group,adolescents were given 300 mg/d LBP.A 6-week follow up was completed by 24 adolescents,comprising 14 adolescents from the LBP group(15.36±2.06 years,3 men and 11 women)and 10 adolescents from the placebo group(14.9±1.6 years,2 men and 8 women).Our results showed that after 6 weeks of treatment,the interleukin-17A level in the LBP group was lower than that in the placebo group.Network analysis showed that LBP reduced the correlations and connectivity between inflammatory factors,which were associated with the improvement in depressive symptoms.These findings suggest that 6-week administration of LBP suppresses the immune response by reducing interleukin-17A level,thereby exerting an antidepressant effect. 展开更多
关键词 adolescents CYTOKINES EFFICACY Goji berry inflammatory responses INTERLEUKIN-17A Lycium barbarum polysaccharide randomized controlled study subthreshold depression
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Effect of viral hepatitis on type 2 diabetes:A Mendelian randomization study
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作者 Yun-Feng Yu Gang Hu +3 位作者 Ke-Ke Tong Xin-Yu Yang Jing-Yi Wu Rong Yu 《World Journal of Diabetes》 SCIE 2024年第2期220-231,共12页
BACKGROUND The effects of viral hepatitis(VH)on type 2 diabetes(T2D)remain controversial.AIM To analyze the causal correlation between different types of VH and T2D using Mendelian randomization(MR).METHODS Single nuc... BACKGROUND The effects of viral hepatitis(VH)on type 2 diabetes(T2D)remain controversial.AIM To analyze the causal correlation between different types of VH and T2D using Mendelian randomization(MR).METHODS Single nucleotide polymorphisms of VH,chronic hepatitis B(CHB),chronic hepatitis C(CHC)and T2D were obtained from the BioBank Japan Project,European Bioinformatics Institute,and FinnGen.Inverse variance weighted,MREgger,and weighted median were used to test exposure-outcome associations.The MR-Egger intercept analysis and Cochran’s Q test were used to assess horizontal pleiotropy and heterogeneity,respectively.Leave-one-out sensitivity analysis was used to evaluate the robustness of the MR analysis results.RESULTS The MR analysis showed no significant causal relationship between VH and T2D in Europeans[odds ratio(OR)=1.028;95%confidence interval(CI):0.995-1.062,P=0.101].There was a negative causal association between CHB and T2D among East Asians(OR=0.949;95%CI:0.931-0.968,P<0.001),while there was no significant causal association between CHC and T2D among East Asians(OR=1.018;95%CI:0.959-1.081,P=0.551).Intercept analysis and Cochran’s Q test showed no horizontal pleiotropy or heterogeneity(P>0.05).Sensitivity analysis showed that the results were robust.CONCLUSION Among East Asians,CHB is associated with a reduced T2D risk,but this association is limited by HBV load and cirrhosis.Although VH among Europeans and CHC among East Asians are not associated with the risk of T2D,focusing on blood glucose in patients with CHC is still relevant for the early detection of T2D induced by CHCmediated pathways of hepatic steatosis,liver fibrosis,and cirrhosis. 展开更多
关键词 Viral hepatitis Chronic hepatitis B Chronic hepatitis C Type 2 diabetes Mendelian randomization
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The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis
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作者 Xueyun Shao Longfei He Yangyang Liu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1513-1520,共8页
Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase bra... Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67, I^(2) = 0.00%). The combined effect of the interventions was significant(MD = 2.88, 95% CI: 1.53–4.22, P < 0.0001), indicating that the brain-derived neurotrophic factor levels of the children and adolescents in the exercise group were significantly higher than those in the control group. In conclusion, different types of exercise interventions significantly increased brain-derived neurotrophic factor levels in children and adolescents. However, because of the small sample size of this meta-analysis, more high-quality research is needed to verify our conclusions. This metaanalysis was registered at PROSPERO(registration ID: CRD42023439408). 展开更多
关键词 adolescents brain-derived neurotrophic factor CHILDREN EXERCISE META-ANALYSIS randomized controlled trials
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涉海产业类企业融资效率及影响因素测评研究——基于DEA-Random Effects Models的经验数据 被引量:11
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作者 周昌仕 郇长坤 《中国海洋大学学报(社会科学版)》 CSSCI 2015年第2期13-20,共8页
为发展壮大涉海产业类企业并带动海洋产业发展以实现海洋强国战略,有必要对涉海产业类企业融资效率状况进行准确定位并采取相应策略。以企业融资效率理论为基础,运用DEA模型评价涉海产业类企业融资效率及并运用随机效应面板数据模型检... 为发展壮大涉海产业类企业并带动海洋产业发展以实现海洋强国战略,有必要对涉海产业类企业融资效率状况进行准确定位并采取相应策略。以企业融资效率理论为基础,运用DEA模型评价涉海产业类企业融资效率及并运用随机效应面板数据模型检验其影响因素。检验结果发现,2008-2013年间涉海产业类企业融资效率整体上处于低效水平,其主要影响因素有宏观经济形势、行业竞争程度、企业规模大小和公司治理机制。企业融资效率与宏观经济形势、行业竞争程度和公司治理机制显著正相关,与企业规模大小显著负相关。这说明涉海产业类企业还有大幅度提高融资效率的空间,政策建议是引导资本市场支持海洋资源开发利用,保持稳定增长的整体经济环境,促进垄断竞争性涉海产业类企业理性投融资,缓解中小型涉海产业类企业融资难困境和深化国有控股涉海产业类企业改革。 展开更多
关键词 涉海产业类企业 融资效率 资本结构 DEA模型 随机效应模型
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Estimation in Nonlinear Models with Random Effects
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作者 宗序平 朱仲义 《Journal of Southeast University(English Edition)》 EI CAS 1998年第2期124-129,共6页
A necessary condition for existence of any weakly consistent estimator is presented in nonlinear models with random effects. Under mild regularity conditions, the strong consistency and the asymptotic normality of the... A necessary condition for existence of any weakly consistent estimator is presented in nonlinear models with random effects. Under mild regularity conditions, the strong consistency and the asymptotic normality of the estimator are proved. The results of Breslow and Calyton(1993), Lee and Nelder(1996) are improved. 展开更多
关键词 fixed effects random effects marginal likelihood
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Effect of Nonlinear Geometric Behavior on Random Response of Rotational Shell
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作者 高世桥 Niemann H J 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期23-28,共6页
Aimed at the large deformation problem of industry cooling tower shell, the mathematical model for the random response of rotational shell under the external random excitation is established by statistic perturbation ... Aimed at the large deformation problem of industry cooling tower shell, the mathematical model for the random response of rotational shell under the external random excitation is established by statistic perturbation method. The effect of nonlinear geometric behavior on the response of rotational shell is analyzed. 展开更多
关键词 nonlinear behavior random response rotational shell cooling tower
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INFLUENCE ANALYSIS IN NONLINEAR MODELS WITH RANDOM EFFECTS 被引量:4
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作者 Wei Bocheng Zhong Xuping Dept. of Appl. Math., Southeast Univ., Nanning 210096. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期35-44,共10页
In this paper,a unified diagnostic method for the nonlinear models with random effects based upon the joint likelihood given by Robinson in 1991 is presented.It is shown that the case deletion model is equivalent to t... In this paper,a unified diagnostic method for the nonlinear models with random effects based upon the joint likelihood given by Robinson in 1991 is presented.It is shown that the case deletion model is equivalent to the mean shift outlier model.From this point of view,several diagnostic measures,such as Cook distance,score statistics are derived.The local influence measure of Cook is also presented. A numerical example illustrates that the method is available. 展开更多
关键词 Cook distance nonlinear models fixed effects local influence random effects.
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EMPIRICAL BAYES TEST PROBLEMS OF VARIANCE COMPONENTS IN RANDOM EFFECTS MODEL 被引量:3
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作者 韦来生 张伟平 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期274-282,共9页
Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that t... Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that the proposed EB decision rules are asymptotically optimal with convergence rates near O(n-1/2). Finally, an example concerning the main result is given. 展开更多
关键词 Empirical Bayes test variance components random effects model convergence rates
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TESTING FOR VARYING DISPERSION OF LONGITUDINAL BINOMIAL DATA IN NONLINEAR LOGISTIC MODELS WITH RANDOM EFFECTS 被引量:2
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作者 林金官 韦博成 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期559-568,共10页
In this paper, it is discussed that two tests for varying dispersion of binomial data in the framework of nonlinear logistic models with random effects, which are widely used in analyzing longitudinal binomial data. O... In this paper, it is discussed that two tests for varying dispersion of binomial data in the framework of nonlinear logistic models with random effects, which are widely used in analyzing longitudinal binomial data. One is the individual test and power calculation for varying dispersion through testing the randomness of cluster effects, which is extensions of Dean(1992) and Commenges et al (1994). The second test is the composite test for varying dispersion through simultaneously testing the randomness of cluster effects and the equality of random-effect means. The score test statistics are constructed and expressed in simple, easy to use, matrix formulas. The authors illustrate their test methods using the insecticide data (Giltinan, Capizzi & Malani (1988)). 展开更多
关键词 Longitudinal binomial data logistic regression nonlinear models power calculation random effects score test varying dispersion
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INFLUENCE ANALYSIS ON EXPONENTIAL NONLINEAR MODELS WITH RANDOM EFFECTS 被引量:2
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作者 宗序平 赵俊 +1 位作者 王海斌 韦博成 《Acta Mathematica Scientia》 SCIE CSCD 2003年第3期297-308,共12页
This paper presents a unified diagnostic method for exponential nonlinear models with random effects based upon the joint likelihood given by Robinson in 1991. The authors show that the case deletion model is equivale... This paper presents a unified diagnostic method for exponential nonlinear models with random effects based upon the joint likelihood given by Robinson in 1991. The authors show that the case deletion model is equivalent to mean shift outlier model. From this point of view, several diagnostic measures, such as Cook distance, score statistics are derived. The local influence measure of Cook is also presented. Numerical example illustrates that our method is available. 展开更多
关键词 Cook distance exponential nonlinear models fixed effects local influence random effects
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Optimal Credibility Estimation of Random Parameters in Hierarchical Random Effect Linear Model 被引量:2
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作者 WEN Limin FANG Jing +1 位作者 MEI Guoping WU Xianyi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第5期1058-1069,共12页
In the hierarchical random effect linear model, the Bayes estimator of random parameter are not only dependent on specific prior distribution but also it is difficult to calculate in most cases. This paper derives the... In the hierarchical random effect linear model, the Bayes estimator of random parameter are not only dependent on specific prior distribution but also it is difficult to calculate in most cases. This paper derives the distributed-free optimal linear estimator of random parameters in the model by means of the credibility theory method. The estimators the authors derive can be applied in more extensive practical scenarios since they are only dependent on the first two moments of prior parameter rather than on specific prior distribution. Finally, the results are compared with some classical models and a numerical example is given to show the effectiveness of the estimators. 展开更多
关键词 Bayes theory credibility estimator hierarchical linear model random effect
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Total ionizing dose and synergistic effects of magnetoresistive random-access memory 被引量:9
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作者 Xing-Yao Zhang Qi Guo +1 位作者 Yu-Dong Li Lin Wen 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第8期136-140,共5页
A magnetoresistive random-access memory(MRAM) device was irradiated by ^(60) Co c-rays and an electron beam.The synergistic effect of this on the MRAM was tested with an additional magnetic field during irradiation,fr... A magnetoresistive random-access memory(MRAM) device was irradiated by ^(60) Co c-rays and an electron beam.The synergistic effect of this on the MRAM was tested with an additional magnetic field during irradiation,from which the total ionizing dose(TID) and the synergistic damage mechanism of MRAM were analyzed.In addition,DC,AC,and functional parameters of the memory were tested under irradiation and annealing via a very large-scale integrated circuit test system.The radiation-sensitive parameters were obtained through analyzing the data.Because of the magnetic field applied on the MRAM while testing the synergistic effects,shallow trench isolation leakage and Frenkel–Poole emission due to synergistic effects were smaller than that of TID,and hence radiation damage of the synergistic effects was also lower. 展开更多
关键词 随机存取 剂量 电离 记忆 集成电路测试 MRAM TID 存储器
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Effects of premedication with Pronase for endoscopic ultrasound of the stomach: A randomized controlled trial 被引量:8
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作者 Guo-Xin Wang Xiang Liu +3 位作者 Sheng Wang Nan Ge Jin-Tao Guo Si-Yu Sun 《World Journal of Gastroenterology》 SCIE CAS 2016年第48期10673-10679,共7页
AIM To analyze the effects of premedication with Pronase for endoscopic ultrasound(EUS) examination of the stomach.METHODS This was a prospective, randomized and controlled clinical study. All patients were randomly a... AIM To analyze the effects of premedication with Pronase for endoscopic ultrasound(EUS) examination of the stomach.METHODS This was a prospective, randomized and controlled clinical study. All patients were randomly assigned to either the Pronase group or placebo group. The pretreatment solution was a mixed solution of 20000 U of Pronase and 60 m L sodium bicarbonate solution in the Pronase group, while an equal amount of sodium bicarbonate solution was administered to the placebo group. All operators, image evaluators and experimental recorders in EUS did not participate in the preparation and allocation of pretreatment solution. Two blinded investigators assessed the obscurity scores for the EUS images according to the size of artifacts(including ultrasound images of the gastric cavity and the gastric wall). Differences in imaging quality, the duration of examination and the usage of physiological saline during the examination process between the Pronase group and the control group were compared.RESULTS No differences existed in patient demographics between the two groups. For the gastric cavity, the Pronase group had significantly lower mean obscurity scores than the placebo group(1.0476 ± 0.77 vs 1.6129 ± 0.96, respectively, P = 0.000). The mean obscurity scores for the gastric mucosal surface were significantly lower in the Pronase group than the placebo group(1.2063 ± 0.90 vs 1.7581 ± 0.84, respectively, P = 0.001). The average EUS procedure duration for the Pronase group was 11.60 ± 3.32 min, which was significantly shorter than that of the placebo group(13.13 ± 3.81 min, P = 0.007). Less saline was used in the Pronase group than the placebo group, and the difference was significant(417.94 ± 121.38 m L vs 467.42 ± 104.52 mL, respectively, P = 0.016).CONCLUSION The group that had Pronase premedication prior to the EUS examination had clearer images than the placebo group. With Pronase premedication, the examination time was shorter, and the amount of saline used during the EUS examination was less. 展开更多
关键词 ARTIFACTS randomIZED controlled trial ENDOSONOGRAPHY PRONASE STOMACH
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Functional and psychosocial effects of pulmonary Daoyin on patients with COPD in China:study protocol of a multicenter randomized controlled trial 被引量:15
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作者 Xue-qing Yu Jian-sheng Li +5 位作者 Su-yun Li Yang Xie Ming-hang Wang Hai-long Zhang Hai-feng Wang Zhi-wan Wang 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第2期140-146,共7页
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major public health problem worldwide. Pulmonary rehabilitation (PR) is an established intervention for the management of patients with COPD. Exercise... BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major public health problem worldwide. Pulmonary rehabilitation (PR) is an established intervention for the management of patients with COPD. Exercise training is an important part of PR, and its effectiveness in patients with COPD is well established. However, alternative methods of PR training such as Daoyin have not been appropriately studied. Hence, alternative forms of exercise training that require less exercise equipment and no specific training place should be evaluated. This paper describes the study protocol of a clinical trial that aims to determine if pulmonary Daoyin training will improve the exercise capacity and psychosocial function of patients with COPD in China. METHODS AND DESIGN: A multicenter, randomized, controlled trial will be conducted. A total of 464 patients meeting the inclusion criteria will be enrolled into this study with 232 patients in each of the trial group and the control group. Based on patient education, patients in the trial group will receive pulmonary Daoyin and continue with their usual therapy for three months. In the control group, patients will continue with their usual therapy. The primary outcome measures are exercise capacity assessed by the six-minute walking distance test and lung function. Secondary outcomes include dyspnea and quality of life. Measurements will be taken at baseline (month 0) and after the study period (month 3). DISCUSSION: It is hypothesized that pulmonary Daoyin will have beneficial effects in improving exercise capacity and psychosocial function of patients with stable COPD, and will provide an alternative form of exercise training that is accessible for the large number of people with COPD. TRIAL REGISTRATION: This trial has been registered in ClinicalTrials.gov. The identifier is NCT01482000. 展开更多
关键词 chronic obstructive pulmonary disease DAOYIN randomized controlled trial study protocol
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Effect of Pump Area on Lasing Modes in Active Random Media 被引量:6
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作者 谢应茂 刘正东 《Chinese Physics Letters》 SCIE CAS CSCD 2005年第11期2827-2830,共4页
We investigate the effect of pump area on lasing modes in an active random medium. Considering the structure characteristics in a real experimental system, the random medium is divided into two regions, i.e. pump and ... We investigate the effect of pump area on lasing modes in an active random medium. Considering the structure characteristics in a real experimental system, the random medium is divided into two regions, i.e. pump and non-pump areas. The dependence of lasing modes on the pump area is qualitatively explained by means of the model in which the lasing is ascribed to the interaction of the complex localized modes in the active random medium with local aperiodic quasi-structure with appropriate pump light. There exist different pump sizes for lasing with different modes. As the pump size decreases in this random system, the pump threshold of the lasing modes increases. There are different lasing modes in different excitation regions in this random system. This gives us some information about the dependence of lasing modes on pump areas in active random media. 展开更多
关键词 random LASERS SCATTERING MEDIA LIGHT GENERATION
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