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Bayesian Posterior Predictive Probability Happiness
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作者 Gabriela Rodríguez-Hernández Galileo Domínguez-Zacarías Carlos Juárez Lugo 《Applied Mathematics》 2016年第8期753-764,共12页
We propose to determine the underlying causal structure of the elements of happiness from a set of empirically obtained data based on Bayesian. We consider the proposal to study happiness as a multidimensional constru... We propose to determine the underlying causal structure of the elements of happiness from a set of empirically obtained data based on Bayesian. We consider the proposal to study happiness as a multidimensional construct which converges four dimensions with two different Bayesian techniques, in the first we use the Bonferroni correction to estimate the mean multiple comparisons, on this basis it is that we use the function t and a z-test, in both cases the results do not vary, so it is decided to present only those shown by the t test. In the Bayesian Multiple Linear Regression, we prove that happiness can be explained through three dimensions. The technical numerical used is MCMC, of four samples. The results show that the sample has not atypical behavior too and that suitable modifications can be described through a test. Another interesting result obtained is that the predictive probability for the case of sense positive of life and personal fulfillment dimensions exhibit a non-uniform variation. 展开更多
关键词 bayesian Inference posterior Predictive Distribution MCMC HAPPINESS
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A Novel Attack Graph Posterior Inference Model Based on Bayesian Network 被引量:6
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作者 Shaojun Zhang Shanshan Song 《Journal of Information Security》 2011年第1期8-27,共20页
Network attack graphs are originally used to evaluate what the worst security state is when a concerned net-work is under attack. Combined with intrusion evidence such like IDS alerts, attack graphs can be further use... Network attack graphs are originally used to evaluate what the worst security state is when a concerned net-work is under attack. Combined with intrusion evidence such like IDS alerts, attack graphs can be further used to perform security state posterior inference (i.e. inference based on observation experience). In this area, Bayesian network is an ideal mathematic tool, however it can not be directly applied for the following three reasons: 1) in a network attack graph, there may exist directed cycles which are never permitted in a Bayesian network, 2) there may exist temporal partial ordering relations among intrusion evidence that can-not be easily modeled in a Bayesian network, and 3) just one Bayesian network cannot be used to infer both the current and the future security state of a network. In this work, we improve an approximate Bayesian posterior inference algorithm–the likelihood-weighting algorithm to resolve the above obstacles. We give out all the pseudocodes of the algorithm and use several examples to demonstrate its benefit. Based on this, we further propose a network security assessment and enhancement method along with a small network scenario to exemplify its usage. 展开更多
关键词 NETWORK Security ATTACK Graph posterior INFERENCE bayesian NETWORK Likelihood-Weighting
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基于BP-Bayesian方法的河网糙率反演 被引量:8
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作者 张潮 毛根海 +2 位作者 张土乔 朱嵩 程伟平 《江苏大学学报(自然科学版)》 EI CAS 北大核心 2008年第1期47-51,共5页
引进BP神经网络优化Bayesian方法中似然函数的计算,得到一种新的BP-Bayesian方法,用来反演河网中各河段糙率.通过一个9河段组成的河网算例,使用本方法得到各河段糙率的后验分布和估计值,最大误差不超过3%;在测量值出现校准误差时,也能... 引进BP神经网络优化Bayesian方法中似然函数的计算,得到一种新的BP-Bayesian方法,用来反演河网中各河段糙率.通过一个9河段组成的河网算例,使用本方法得到各河段糙率的后验分布和估计值,最大误差不超过3%;在测量值出现校准误差时,也能有效给出合理的估计值.BP-Bayesian方法能得到糙率估计值的概率密度分布,并从中得到有效的估计值,避免了传统优化方法容易陷入局部最优的缺点;同时,与传统Bayesian方法相比能节省大量计算时间. 展开更多
关键词 河网糙率 BP-bayesian方法 反演 后验分布
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改进Bayesian后验比的异常风速值检测方法 被引量:2
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作者 陈伟 吴布托 +1 位作者 裴喜平 王懿喆 《电网与清洁能源》 北大核心 2017年第2期104-111,116,共9页
风电场运行数据中含有异常风速值,为了优化风电数据的质量,提出了组合预测与Bayesian后验比的异常值检测方法。为了降低预测误差,先对风速序列建立Adaboost-BP网络和EMD-LV-SVM的组合预测模型,利用预测值与测量值的偏差得到含有粗大误... 风电场运行数据中含有异常风速值,为了优化风电数据的质量,提出了组合预测与Bayesian后验比的异常值检测方法。为了降低预测误差,先对风速序列建立Adaboost-BP网络和EMD-LV-SVM的组合预测模型,利用预测值与测量值的偏差得到含有粗大误差的残差序列;为了提高检测方法的可靠性,采用Bayesian后验比的检验方法识别残差序列中粗大误差,从而确定异常风速值的位置,并利用ARIMA方法修正异常风速值。RBF预测结果表明,所提方法能准确识别异常值,从而提高了风电场短期风速预测精度。 展开更多
关键词 异常风速值检测 组合预测模型 残差分 bayesian后验比
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散乱点数据的Bayesian曲面重建
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作者 杨军 邢琪 +1 位作者 诸昌钤 彭强 《计算机应用》 CSCD 北大核心 2007年第10期2522-2524,2529,共4页
针对带噪声的点云数据提出了一种基于贝叶斯(Bayesian)统计理论的曲面重建算法。算法的主要思想是在可能的重建概率空间上寻找最大后验概率。首先,分别计算测量过程数学模型和曲面先验概率模型;其次,通过共轭梯度优化算法确定每一个点... 针对带噪声的点云数据提出了一种基于贝叶斯(Bayesian)统计理论的曲面重建算法。算法的主要思想是在可能的重建概率空间上寻找最大后验概率。首先,分别计算测量过程数学模型和曲面先验概率模型;其次,通过共轭梯度优化算法确定每一个点的最大后验重建位置;最后,应用Surface Splatting算法绘制点模型。实验结果表明,该先验概率模型不仅能去除扫描点云数据的噪声,同时还能增强曲面的细节特征。和已有的研究工作相比,本算法能获得更好的重建结果。 展开更多
关键词 贝叶斯方法 后验 先验 测量模型 Surface SPLATTING 点模型
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基于Bayesian分析的垂穗披碱草根系力学特性估计方法 被引量:1
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作者 付江涛 郭鸿 +3 位作者 李晓康 胡夏嵩 刘昌义 李希来 《农业工程学报》 EI CAS CSCD 北大核心 2023年第22期112-120,共9页
植物根系力学特性是度量植物根系对土体抗剪强度贡献,评价植物根系提高土壤抗侵蚀性和边坡稳定性的重要指标之一。该研究基于Bayesian分析,选取生长于青海天峻县江仓矿区排土场人工种植的垂穗披碱草(Elymusnutans Griseb.)为研究对象,... 植物根系力学特性是度量植物根系对土体抗剪强度贡献,评价植物根系提高土壤抗侵蚀性和边坡稳定性的重要指标之一。该研究基于Bayesian分析,选取生长于青海天峻县江仓矿区排土场人工种植的垂穗披碱草(Elymusnutans Griseb.)为研究对象,在对其根系力学特性进行测定基础上,以测得的28组根系力学特性的期望值和方差为先验信息,以第29组根系力学特性测定值为样本信息,建立了用于计算该区域垂穗披碱草根系力学特性的正态-逆伽马后验分布,并分别计算了先验分布的超参数以及后验分布中的分布参数。研究结果表明,先验信息中,除极限拉伸应变外,其余指标均值的期望值变异性均较小且各指标的均值均服从正态分布,方差的倒数则满足伽马分布,而各指标的样本分布满足正态分布,故可通过正态-逆伽马分布对区内垂穗披碱草根系力学特性的后验分布进行描述;后验信息概率密度曲线与样本信息概率密度曲线几何形状较为相似,该结果说明后验信息更倾向于样本信息,且得到的结果亦可由柯尔莫哥洛夫-斯米洛夫检验予以佐证。此外,样本数量与先验信息离散度决定了先验均值和样本均值在决定后验均值时所占的权重。在其他条件不变的情况下,样本数量越大则样本所占权重越大。该研究可为准确计算植物根系力学特性提供思路和研究方法。 展开更多
关键词 力学特性 正态分布 根系 贝叶斯分析 后验信息 先验信息
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基于层次Bayesian网络及后验风险准则的故障样本量确定方法 被引量:5
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作者 史贤俊 王康 +1 位作者 韩旭 龙玉峰 《兵工学报》 EI CAS CSCD 北大核心 2019年第1期171-181,共11页
针对现有测试性验证方法对装备系统结构考虑不足,且在双方风险约束条件下所确定的故障样本量过大问题,提出一种基于层次Bayesian网络和后验风险准则的故障样本量确定方法。根据装备系统结构建立测试性验证方法的层次Bayesian网络模型,... 针对现有测试性验证方法对装备系统结构考虑不足,且在双方风险约束条件下所确定的故障样本量过大问题,提出一种基于层次Bayesian网络和后验风险准则的故障样本量确定方法。根据装备系统结构建立测试性验证方法的层次Bayesian网络模型,并以故障检测率作为Bayesian网络的传递参数;提出Bayesian网络不确定性推理算法,充分融合各层次测试性先验信息,同时基于偏度-峰度检验的拟合分布选取方法推导出系统故障检测率联合先验分布;进一步结合系统成败型数据确定其后验分布,基于后验样本数据集和Bayes后验风险准则设计故障样本量确定算法,通过实例进行分析。结果表明,与经典验证方法、传统Bayesian方法相比,所提方法在相同双方指标约束下能有效降低样本量。 展开更多
关键词 层次bayesian网络 后验风险准则 测试性 测试性验证 故障样本量 故障检测率
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基于非局部方向性核先验的PET图像Bayesian重建
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作者 李印生 陈阳 +3 位作者 罗立民 陈武凡 陈芳 宋培维 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第5期937-942,共6页
为了在抑制噪声的同时更好地保持PET重建图像中的细节结构,提出了一种基于非局部方向性核先验(NSKP)的Bayesian重建算法.为了充分利用图像中的全局信息,该算法在二阶核回归过程中估计出图像梯度,计算出相应的方向性矩阵,并根据非局部均... 为了在抑制噪声的同时更好地保持PET重建图像中的细节结构,提出了一种基于非局部方向性核先验(NSKP)的Bayesian重建算法.为了充分利用图像中的全局信息,该算法在二阶核回归过程中估计出图像梯度,计算出相应的方向性矩阵,并根据非局部均值权值矩阵和方向性矩阵的卷积,计算先验项的权值.在重建中,该算法在高阶核回归过程中同时更新图像的梯度和先验信息,而不是单独计算图像梯度.另外,高阶核回归方法运用多自由度的参数估计提高了重建的精确度.研究结果表明,该算法通过计算引入局部结构信息的全局先验权重,更好地抑制了噪声和过平滑,保持了重建图像中细节区域的结构性和背景区域的一致性.对体模数据的模拟实验结果从视觉和数值角度验证了该算法在PET图像重建中的有效性. 展开更多
关键词 bayesian-MAP 非局部方向性核先验 方向性矩阵 高阶核回归 结构自适应重建
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Research on Test Data Distribution of Strapdown Inertial Measurement Unit Based on Bayesian Method 被引量:1
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作者 徐军辉 汪立新 钱培贤 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第3期214-217,共4页
Aiming at that the successive test data set of the strapdown inertial measurement unit is always small,a Bayesian method is used to study its statistical characteristics.Its prior and posterior distributions are set u... Aiming at that the successive test data set of the strapdown inertial measurement unit is always small,a Bayesian method is used to study its statistical characteristics.Its prior and posterior distributions are set up by the method and the pretest,sample and population information.Some statistical inferences can be made based on the posterior distribution.It can reduce the statistical analysis error in the case of small sample set. 展开更多
关键词 战术导弹 数学统计学 惯性测量 技术性能
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Bayesian Inference of Empirical Coefficient for Foundation Settlement 被引量:1
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作者 李珍玉 王永和 杨果林 《Journal of Southwest Jiaotong University(English Edition)》 2009年第4期314-318,共5页
A new approach based on Bayesian theory is proposed to determine the empirical coefficient in soil settlement calculation. Prior distribution is assumed to he uniform in [ 0.2,1.4 ]. Posterior density function is deve... A new approach based on Bayesian theory is proposed to determine the empirical coefficient in soil settlement calculation. Prior distribution is assumed to he uniform in [ 0.2,1.4 ]. Posterior density function is developed in the condition of prior distribution combined with the information of observed samples at four locations on a passenger dedicated fine. The results show that the posterior distribution of the empirical coefficient obeys Gaussian distribution. The mean value of the empirical coefficient decreases gradually with the increasing of the load on ground, and variance variation shows no regularity. 展开更多
关键词 bayesian theory Empirical coefficient Prior knowledge posterior distribution
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Bayesian Analysis of Small Multi-frequency Investment of Agricultural Products
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作者 Fengying WANG 《Asian Agricultural Research》 2015年第12期9-11,共3页
The risk decision of small multi-frequency investment mode of agricultural products is studied based on Bayesian method. This method can take advantage of new market information reasonably,analyze the posterior risk a... The risk decision of small multi-frequency investment mode of agricultural products is studied based on Bayesian method. This method can take advantage of new market information reasonably,analyze the posterior risk and quantify the decision risk. It provides a scientific way for the risk decision of agricultural enterprises and is advantageous to enhancing the benefit of project. 展开更多
关键词 Agricultural products bayesian decision posterior information EXPECTED loss
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Bayesian and hierarchical Bayesian analysis of response - time data with concomitant variables
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作者 Dinesh Kumar 《Journal of Biomedical Science and Engineering》 2010年第7期711-718,共8页
This paper considers the Bayes and hierarchical Bayes approaches for analyzing clinical data on response times with available values for one or more concomitant variables. Response times are assumed to follow simple e... This paper considers the Bayes and hierarchical Bayes approaches for analyzing clinical data on response times with available values for one or more concomitant variables. Response times are assumed to follow simple exponential distributions, with a different parameter for each patient. The analyses are carried out in case of progressive censoring assuming squared error loss function and gamma distribution as priors and hyperpriors. The possibilities of using the methodology in more general situations like dose- response modeling have also been explored. Bayesian estimators derived in this paper are applied to lung cancer data set with concomitant variables. 展开更多
关键词 BAYES ESTIMATOR bayesian posterior DENSITY Gamma Prior DENSITY (GPD) HIERARCHICAL BAYES ESTIMATOR Hyperprior Noninformative Prior Quasi-Density (NPQD) Progressive Censoring Squared Error Loss FUNCTION (SELF) Whittaker FUNCTION W s1 s2 (.).
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Extending the Behrens-Fisher Problem to Testing Equality of Slopes in Linear Regression: The Bayesian Approach
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作者 Mohamed Shoukri Futwan Al-Mohanna 《Open Journal of Statistics》 2018年第2期284-301,共18页
Testing the equality of means of two normally distributed random variables when their variances are unequal is known in the statistical literature as the “Behrens-Fisher problem”. It is well-known that the posterior... Testing the equality of means of two normally distributed random variables when their variances are unequal is known in the statistical literature as the “Behrens-Fisher problem”. It is well-known that the posterior distributions of the parameters of interest are the primitive of Bayesian statistical inference. For routine implementation of statistical procedures based on posterior distributions, simple and efficient approaches are required. Since the computation of the exact posterior distribution of the Behrens-Fisher problem is obtained using numerical integration, several approximations are discussed and compared. Tests and Bayesian Highest-Posterior Density (H.P.D) intervals based upon these approximations are discussed. We extend the proposed approximations to test of parallelism in simple linear regression models. 展开更多
关键词 bayesian Inference posterior DISTRIBUTIONS Behrens-Fisher Problem posterior MOMENTS Edgeworth Expansion Monte-Carlo Integration
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Bayesian Set Estimation with Alternative Loss Functions: Optimality and Regret Analysis
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作者 Fulvio De Santis Stefania Gubbiotti 《Open Journal of Statistics》 2023年第2期195-211,共17页
Decision-theoretic interval estimation requires the use of loss functions that, typically, take into account the size and the coverage of the sets. We here consider the class of monotone loss functions that, under qui... Decision-theoretic interval estimation requires the use of loss functions that, typically, take into account the size and the coverage of the sets. We here consider the class of monotone loss functions that, under quite general conditions, guarantee Bayesian optimality of highest posterior probability sets. We focus on three specific families of monotone losses, namely the linear, the exponential and the rational losses whose difference consists in the way the sizes of the sets are penalized. Within the standard yet important set-up of a normal model we propose: 1) an optimality analysis, to compare the solutions yielded by the alternative classes of losses;2) a regret analysis, to evaluate the additional loss of standard non-optimal intervals of fixed credibility. The article uses an application to a clinical trial as an illustrative example. 展开更多
关键词 bayesian Inference Decision-Theoretic Approach Highest posterior Density Sets Interval Estimation REGRET
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Bayesian Inference and Prediction of Burr Type XII Distribution for Progressive First Failure Censored Sampling 被引量:1
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作者 Ahmed A. Soliman A. H. Abd Ellah +1 位作者 N. A. Abou-Elheggag A. A. Modhesh 《Intelligent Information Management》 2011年第5期175-185,共11页
This paper deals with Bayesian inference and prediction problems of the Burr type XII distribution based on progressive first failure censored data. We consider the Bayesian inference under a squared error loss functi... This paper deals with Bayesian inference and prediction problems of the Burr type XII distribution based on progressive first failure censored data. We consider the Bayesian inference under a squared error loss function. We propose to apply Gibbs sampling procedure to draw Markov Chain Monte Carlo (MCMC) samples, and they have in turn, been used to compute the Bayes estimates with the help of importance sampling technique. We have performed a simulation study in order to compare the proposed Bayes estimators with the maximum likelihood estimators. We further consider two sample Bayes prediction to predicting future order statistics and upper record values from Burr type XII distribution based on progressive first failure censored data. The predictive densities are obtained and used to determine prediction intervals for unobserved order statistics and upper record values. A real life data set is used to illustrate the results derived. 展开更多
关键词 BURR TYPE XII DISTRIBUTION PROGRESSIVE First-Failure Censored Sample bayesian Estimations Gibbs Sampling Markov Chain Monte Carlo posterior Predictive Density
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Unlocking New Paths for Efficient Analysis of Gravitational Waves from Extreme-Mass-Ratio Inspirals with Machine Learning
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作者 Bo Liang Hong Guo +11 位作者 Tianyu Zhao He Wang Herik Evangelinelis Yuxiang Xu Chang Liu Manjia Liang Xiaotong Wei Yong Yuan Minghui Du Peng Xu Weiliang Qian Ziren Luo 《Chinese Physics Letters》 2025年第8期370-378,共9页
Extreme-mass-ratio inspiral(EMRI)signals pose significant challenges to gravitational wave(GW)data analysis,mainly owing to their highly complex waveforms and high-dimensional parameter space.Given their extended time... Extreme-mass-ratio inspiral(EMRI)signals pose significant challenges to gravitational wave(GW)data analysis,mainly owing to their highly complex waveforms and high-dimensional parameter space.Given their extended timescales of months to years and low signal-to-noise ratios,detecting and analyzing EMRIs with confidence generally relies on long-term observations.Besides the length of data,parameter estimation is particularly challenging due to non-local parameter degeneracies,arising from multiple local maxima,as well as flat regions and ridges inherent in the likelihood function.These factors lead to exceptionally high time complexity for parameter analysis based on traditional matched filtering and random sampling methods.To address these challenges,the present study explores a machine learning approach to Bayesian posterior estimation of EMRI signals,leveraging the recently developed flow matching technique based on ordinary differential equation neural networks.To our knowledge,this is also the first instance of applying continuous normalizing flows to EMRI analysis.Our approach demonstrates an increase in computational efficiency by several orders of magnitude compared to the traditional Markov chain Monte Carlo(MCMC)methods,while preserving the unbiasedness of results.However,we note that the posterior distributions generated by FMPE may exhibit broader uncertainty ranges than those obtained through full Bayesian sampling,requiring subsequent refinement via methods such as MCMC.Notably,when searching from large priors,our model rapidly approaches the true values while MCMC struggles to converge to the global maximum.Our findings highlight that machine learning has the potential to efficiently handle the vast EMRI parameter space of up to seventeen dimensions,offering new perspectives for advancing space-based GW detection and GW astronomy. 展开更多
关键词 machine learning extreme mass ratio inspirals analyzing emris flow matching bayesian posterior estimation parameter estimation gravitational waves normalizing flows
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A Bayesian Mixture Model Approach to Disparity Testing
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作者 Gary C. McDonald 《Applied Mathematics》 2024年第3期214-234,共21页
The topic of this article is one-sided hypothesis testing for disparity, i.e., the mean of one group is larger than that of another when there is uncertainty as to which group a datum is drawn. For each datum, the unc... The topic of this article is one-sided hypothesis testing for disparity, i.e., the mean of one group is larger than that of another when there is uncertainty as to which group a datum is drawn. For each datum, the uncertainty is captured with a given discrete probability distribution over the groups. Such situations arise, for example, in the use of Bayesian imputation methods to assess race and ethnicity disparities with certain insurance, health, and financial data. A widely used method to implement this assessment is the Bayesian Improved Surname Geocoding (BISG) method which assigns a discrete probability over six race/ethnicity groups to an individual given the individual’s surname and address location. Using a Bayesian framework and Markov Chain Monte Carlo sampling from the joint posterior distribution of the group means, the probability of a disparity hypothesis is estimated. Four methods are developed and compared with an illustrative data set. Three of these methods are implemented in an R-code and one method in WinBUGS. These methods are programed for any number of groups between two and six inclusive. All the codes are provided in the appendices. 展开更多
关键词 bayesian Improved Surname and Geocoding (BISG) Mixture Likelihood Function posterior Distribution Metropolis-Hastings Algorithms Random Walk Chain Independence Chain Gibbs Sampling WINBUGS
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以标注确定性增强为导向的正类-无标签学习算法
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作者 何玉林 何芃 +2 位作者 黄哲学 解为成 PHILIPPE Fournier-Viger 《计算机应用》 北大核心 2025年第7期2101-2112,共12页
正类-无标签学习(PUL)是在负例样本未知时,利用已知的少量正类样本和大量无标签样本训练出性能可被实际应用接受的分类器。现有的PUL算法存在共性的缺陷,即对无标签样本标注的不确定性较大,这将导致分类器学习到的分类边界不准确,并且... 正类-无标签学习(PUL)是在负例样本未知时,利用已知的少量正类样本和大量无标签样本训练出性能可被实际应用接受的分类器。现有的PUL算法存在共性的缺陷,即对无标签样本标注的不确定性较大,这将导致分类器学习到的分类边界不准确,并且限制了所训练分类器在新数据上的泛化能力。为了解决这一问题,提出一种以无标签样本标注确定性增强为导向的PUL(LCE-PUL)算法。首先,通过验证集的后验概率均值和正类样本集中心点的相似程度筛选出可靠的正类样本,并通过多轮迭代逐步精细化标注过程,以提升对无标签样本初步类别判断的准确性,从而提高无标签样本标注的确定性;其次,把这些可靠的正类样本与原始正类样本集合并,以形成新的正类样本集,之后从无标签样本集中将它剔除;然后,遍历新的无标签样本集,并利用每个样本与若干近邻点的相似程度再次筛选可靠正类样本,以更准确地推断无标签样本的潜在标签,从而减少误标注的可能性,并提升标注的确定性;最后,更新正类样本集,并把未被选中的无标签样本视为负类样本。在具有代表性的数据集上对LCE-PUL算法的可行性、合理性和有效性进行验证。随着迭代次数的增加,LCE-PUL算法的训练呈现收敛的特性,且当正类样本比例为40%、35%和30%时,LCE-PUL算法构建的分类器测试精度相较于基于特定成本函数的偏置支持向量机(BiasedSVM)算法、基于Dijkstra的PUL标签传播(LP-PUL)算法和基于标签传播的PUL(PU-LP)算法等5种代表性对比算法中最多提升了5.8、8.8和7.6个百分点。实验结果表明,LCE-PUL是一种有效处理PUL问题的机器学习算法。 展开更多
关键词 正类-无标签学习 标注确定性增强 后验概率 贝叶斯分类器 两步法
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基于模糊贝叶斯网络的城市排水管网风险评估
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作者 杨文家 吴良洪 +1 位作者 林卫东 阳富强 《中国安全科学学报》 北大核心 2025年第10期174-180,共7页
为提升城市排水管网的事故预防与风险管控水平,首先,梳理“人-机-管-环”4个方面的指标,得到19项评估指标,构建城市排水管网风险评估指标体系;其次,融合模糊理论与贝叶斯网络(BN)构建城市排水管网风险评估模型,引入三角模糊数量化处理... 为提升城市排水管网的事故预防与风险管控水平,首先,梳理“人-机-管-环”4个方面的指标,得到19项评估指标,构建城市排水管网风险评估指标体系;其次,融合模糊理论与贝叶斯网络(BN)构建城市排水管网风险评估模型,引入三角模糊数量化处理专家评分,基于职称与工龄差异赋予专家权重,并采用α加权估值法将模糊评价转化为清晰概率,开展BN的正反向推理,计算关键节点的后验概率;最后,以某城区排水管网为例,评估该区域排水管网的风险等级,完成现场验证。结果表明:城市排水管网风险评估模型能有效处理风险评估过程中的不确定性与主观性,概率化表征排水管网风险,显著提升评估结果的可靠性;管道的外加保护是影响排水管网安全性的关键因素,防腐措施和接口方式次之;该城市排水管网整体安全性良好,风险处于可控范围;通过与历史监测数据和故障记录的对比分析,验证了该模型具有一定的实用性和可靠性。 展开更多
关键词 贝叶斯网络(BN) 排水管网 风险评估 后验概率 风险等级
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基于上下文敏感贝叶斯网络的角度阈值多元变化检测
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作者 朱睿 李轶鲲 +2 位作者 李小军 杨树文 谢江陵 《自然资源遥感》 北大核心 2025年第5期131-140,共10页
在遥感图像多变化检测领域中,后验概率空间变化向量分析(change vector analysis in posterior probability space,CVAPS)是一种得到广泛使用的变化检测方法。然而,CVAPS利用支持向量机来估计遥感图像像素的后验概率向量,易受到遥感图... 在遥感图像多变化检测领域中,后验概率空间变化向量分析(change vector analysis in posterior probability space,CVAPS)是一种得到广泛使用的变化检测方法。然而,CVAPS利用支持向量机来估计遥感图像像素的后验概率向量,易受到遥感图像中同物异谱、异物同谱、混合像元等因素的影响,从而难以准确估计复杂像元的后验概率向量的强度和方向,并影响了其后多元变化检测的精度。因此,文章在CVAPS的框架下,提出了一种采用模糊C均值聚类分解混合像元,并耦合上下文敏感的贝叶斯网络,使用角度阈值进行多变化类型检测的方法。当夹角小于一定阈值时,则判定该像素为该标准变化向量所代表的变化类型。实验结果证明该算法具有较高变化检测性能,取得了高于对比算法的精度。 展开更多
关键词 角度阈值 多元变化检测 模糊C均值 上下文敏感的贝叶斯网络 后验概率空间 变化向量分析
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