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Bayesian analysis of minimal model under the insulin-modified IVGTT
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作者 Yi Wang Kent M. Eskridge Andrzej T. Galecki 《Health》 2010年第3期188-194,共7页
A Bayesian analysis of the minimal model was proposed where both glucose and insulin were analyzed simultaneously under the insulin-modified intravenous glucose tolerance test (IVGTT). The resulting model was implemen... A Bayesian analysis of the minimal model was proposed where both glucose and insulin were analyzed simultaneously under the insulin-modified intravenous glucose tolerance test (IVGTT). The resulting model was implemented with a nonlinear mixed-effects modeling setup using ordinary differential equations (ODEs), which leads to precise estimation of population parameters by separating the inter- and intra-individual variability. The results indicated that the Bayesian method applied to the glucose-insulin minimal model provided a satisfactory solution with accurate parameter estimates which were numerically stable since the Bayesian method did not require approximation by linearization. 展开更多
关键词 MINIMAL model bayesian Analysis IVGTT Nonlinear mixed-effects modeling ODE
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喀斯特季节性雨林优势树种叶片非结构性碳水化合物空间变异及生态驱动因素 被引量:1
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作者 王斌 钟艺倩 +9 位作者 杨美雪 吴淼锐 王艳萍 陆芳 陶旺兰 李健星 赵弘明 刘晟源 向悟生 李先琨 《生物多样性》 CSCD 北大核心 2024年第12期69-81,共13页
非结构性碳水化合物(non-structural carbohydrates,NSC)是植物碳收支平衡与响应外界环境变化的重要指标。为明确北热带喀斯特季节性雨林优势植物NSC的空间变异及其生态驱动因素,本研究以不同生境条件下共31个优势树种165株个体为研究对... 非结构性碳水化合物(non-structural carbohydrates,NSC)是植物碳收支平衡与响应外界环境变化的重要指标。为明确北热带喀斯特季节性雨林优势植物NSC的空间变异及其生态驱动因素,本研究以不同生境条件下共31个优势树种165株个体为研究对象,对其叶片NSC及组分(可溶性糖、淀粉)含量进行分析。运用贝叶斯系统发育混合效应模型将NSC变异划分为与物种系统发育相关的和无关的两部分,并探讨了这两部分变异与地形、土壤性质、生物群落特征及叶片功能性状之间的深层联系。结果表明:(1)优势树种叶片NSC及其组分含量在3个生境之间存在显著的空间差异性,总体表现为山顶>中坡>洼地。(2)物种系统发育背景对NSC、淀粉及可溶性糖总变异的解释率分别为53.97%、58.23%和57.88%。生态因子对这三者总变异的解释率分别为48.85%、32.54%和32.64%。值得注意的是,生态因子对可溶性糖变异的影响更多是通过系统发育相关途径(23.15%)实现,而对淀粉变异的影响则更依赖于非系统发育相关途径(26.89%)。(3)叶片厚度、枝条木质密度、南北坡向、比叶面积、群落平均胸径、平均海拔和叶绿素含量等对NSC的积累有显著正向效应,而群落胸高断面积之和与土壤总碳等有显著负向效应。综上所述,喀斯特季节性雨林中优势树种叶片NSC的空间变异既受到物种遗传差异与进化历史的深刻影响,也与一系列生态因子的综合作用密切相关。本研究结果体现了不同生境下植物在碳获取、储存及利用策略上的显著适应性分化,为深入理解喀斯特生态系统的碳循环机制及植物的适应策略提供了新视角。 展开更多
关键词 喀斯特峰丛洼地 贝叶斯系统发育混合效应模型 资源岛理论 喀斯特动力系统 系统发育保守性状
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微卫星技术在绵羊品种级进杂交育种中的应用 被引量:2
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作者 吴江鸿 刘国平 +3 位作者 张文广 李虎山 王文义 李金泉 《黑龙江农业科学》 2008年第1期79-82,共4页
分析了10个微卫星基因座10个微卫星标记在7个绵羊群体(德美♂×当地羊♀级进杂交一代、级进杂交二代、级进杂交三代、德克赛尔、道赛特羊、德国美利奴羊、当地羊)205只绵羊中的遗传多态性。结果表明,这10个微卫星标记在7个绵羊群体... 分析了10个微卫星基因座10个微卫星标记在7个绵羊群体(德美♂×当地羊♀级进杂交一代、级进杂交二代、级进杂交三代、德克赛尔、道赛特羊、德国美利奴羊、当地羊)205只绵羊中的遗传多态性。结果表明,这10个微卫星标记在7个绵羊群体中的等位基因数分别为12、22、26、23、14、21、29、17、24和14,由多态信息含量/有效等位基因数/杂合度可知其中AGLA269的遗传变异最大,BMS1714最小。基于Nei氏距离和共祖遗传距离,采用UPGMA方法构建了系统发生树。该发生树将德美×当地羊级进杂交一代、二代、三代和德国美利奴羊归为一类后又与当地羊聚为一大类,将德克赛尔、道赛特羊归为另一类。绵羊微卫星基因分型技术为检查品种(群体)之间的遗传关系提供了一个有用的工具。 展开更多
关键词 微卫星 遗传多态性 分子系统发生 贝叶斯模型 级进杂交育种
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Posterior propriety of an objective prior for generalized hierarchical normal linear models
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作者 Cong Lin Dongchu Sun Chengyuan Song 《Statistical Theory and Related Fields》 2022年第4期309-326,共18页
Bayesian Hierarchical models has been widely used in modern statistical application.To deal with the data having complex structures,we propose a generalized hierarchical normal linear(GHNL)model which accommodates arb... Bayesian Hierarchical models has been widely used in modern statistical application.To deal with the data having complex structures,we propose a generalized hierarchical normal linear(GHNL)model which accommodates arbitrarily many levels,usual design matrices and'vanilla'covari-ance matrices.Objective hyperpriors can be employed for the GHNL model to express ignorance or match frequentist properties,yet the common objective Bayesian approaches are infeasible or fraught with danger in hierarchical modelling.To tackle this issue,[Berger,J,Sun,D.&Song,C.(2020b).An objective prior for hyperparameters in normal hierarchical models.Journal of Multi-variate Analysis,178,104606.https://doi.org/10.1016/jmva.2020.104606]proposed a particular objective prior and investigated its properties comprehensively.Posterior propriety is important for the choice of priors to guarantee the convergence of MCMC samplers.James Berger conjec-tured that the resulting posterior is proper for a hierarchical normal model with arbitrarily many levels,a rigorous proof of which was not given,however.In this paper,we complete this story and provide an user friendly guidance.One main contribution of this paper is to propose a new technique for deriving an elaborate upper bound on the integrated likelihood but also one uni-fied approach to checking the posterior propriety for linear models.An eficient Gibbs sampling method is also introduced and outperforms other sampling approaches considerably. 展开更多
关键词 Hierarchical linear model linear mixed-effect model objective bayesian analysis posterior propriety Gibbs sampling
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Multi-outcome longitudinal small area estimation-a case study 被引量:1
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作者 Eric Slud Yves Thibaudeau 《Statistical Theory and Related Fields》 2019年第2期136-149,共14页
A recent paper [Thibaudeau, Slud, and Gottschalck (2017). Modeling log-linear conditional probabilities for estimation in surveys. The Annals of Applied Statistics, 11, 680–697] proposed a ‘hybrid’method of survey ... A recent paper [Thibaudeau, Slud, and Gottschalck (2017). Modeling log-linear conditional probabilities for estimation in surveys. The Annals of Applied Statistics, 11, 680–697] proposed a ‘hybrid’method of survey estimation combining coarsely cross-classified design-based survey-weightedtotals in a population with loglinear or generalised-linear model-based conditional probabilitiesfor cells in a finer cross-classification. The models were compared in weighted and unweightedforms on data from the US Survey of Income and Program Participation (SIPP), a large nationallongitudinal survey. The hybrid method was elaborated in a book-chapter [Thibaudeau, Slud,& Cheng (2019). Small-area estimation of cross-classified gross flows using longitudinal survey data. In P. Lynn (Ed.), Methodology of longitudinal surveys II. Wiley] about estimating grossflows in (two-period) longitudinal surveys, by considering fixed versus mixed effect versionsof the conditional-probability models and allowing for 3 or more outcomes in the later-periodcategories used to define gross flows within generalised logistic regression models. The methodology provided for point and interval small-area estimation, specifically area-level two-periodlabour-status gross-flow estimation, illustrated on a US Current Population Survey (CPS) datasetof survey respondents in two successive months in 16 states. In the current paper, that data analysis is expanded in two ways: (i) by analysing the CPS dataset in greater detail, incorporatingmultiple random effects (slopes as well as intercepts), using predictive as well as likelihood metrics for model quality, and (ii) by showing how Bayesian computation (MCMC) provides insightsconcerning fixed- versus mixed-effect model predictions. The findings from fixed-effect analyseswith state effects, from corresponding models with state random effects, and fom Bayes analysisof posteriors for the fixed state-effects with other model coefficients fixed, all confirm each otherand support a model with normal random state effects, independent across states. 展开更多
关键词 bayesian computation Current Population Survey generalised logistic regression gross flows mixed-effects model small-area estimation
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