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1.
基于贝叶斯网的分类器及其在CRM中的应用   总被引:4,自引:0,他引:4  
基于贝叶斯网的分类器因其对不确定性问题有较强的处理能力,因此在CRM客户建模中有其独特的优势。在对朴素贝叶斯分类器、通用贝叶斯网分类器优缺点分析的基础上,引入增强型BN分类器和贝叶斯多网分类器,详细介绍了后者的算法,并将其应用到实际电信CRM客户.建模中,取得较好的效果。  相似文献   

2.
针对现有动态贝叶斯网络结构学习方法具有低效率和低可靠性等问题,基于变量之间的基本依赖关系和依赖分析方法进行动态贝叶斯网络结构学习。建立变量之间依赖关系草图,通过条件独立行检验去除多余的边,使用碰撞识别和条件相对预测能力确定边的方向,便可得到构成动态贝叶斯网络结构的先验网和转换网。该方法在效率和可靠性方面均具有优势。  相似文献   

3.
从高维、稀疏的用户评分数据中构建用户偏好模型,存在迭代计算复杂度高、中间结果规模大和难以实现有效推理等问题。为此,提出一种基于深度信念网(DBN)和贝叶斯网(BN)的用户偏好建模方法。采用DBN对评分数据进行分类,用隐变量表示不能直接观测到的用户偏好,利用含隐变量的BN描述评分数据中蕴含的相关属性间的依赖关系及其不确定性。在MovieLens和大众点评数据集上的实验结果表明,该方法能够有效描述评分数据中与用户偏好相关的各属性间的依赖关系,其精确率和执行效率均高于隐变量模型。  相似文献   

4.
事件诱因是诱导事件发生的因素,从事件特征数据构建事件诱因模型,进行事件诱因估计,是解决舆论控制、精准决策支持和用户行为定向等问题的重要基础.本文以公共突发事件为背景,以贝叶斯网为不确定性知识表示和推理的基本框架,以多值隐变量来描述事件诱因的多个取值,提出一种基于带隐变量贝叶斯网(隐变量模型)的事件诱因模型构建方法,进而利用概率推理算法估计事件诱因.针对事件诱因存在多个取值的问题,本文基于分支限界思想提出最优取值子集提取算法.建立在真实数据集上的实验结果表明,本文提出的事件诱因模型构建方法及相应的诱因估计方法是有效的.  相似文献   

5.
贝叶斯网络是用来表示变量集合概率分布的图形模式,它提供了一种方便地表示概率信息的方法,它可以表示因果关系,但并不局限于因果关系。贝叶斯网对不确定性问题有很强的推理能力,近几年来受到众多研究者的重视。贝叶斯网络中弧的定向是指在已经有了变量之间的依赖关系图的条件下确定变量之间的边的方向的过程。介绍了一种改进了贝叶斯网弧定向的方法,该方法结合了目前多种定向方法的优点,实验证明该算法优于已存在的弧定向方法。  相似文献   

6.
贝叶斯网学习算法模型及参数学习算法   总被引:1,自引:0,他引:1  
1 引言近年来,贝叶斯网(又称随机信息网)作为处理人工智能中不确定性问题的建模工具受到学术界的广泛关注,并成功地应用在医学诊断、模式识别、故障诊断各个方面。作为一种有向图表示的建模方法,贝叶斯网由于其表达方式自然、紧凑,深受知识工程师喜受,已广泛地用于知识获取和表示。但是,利用专家知识构造贝叶斯网是一件烦琐的工作,特别是网络节点数很大时更是这样。因此,利用数据例子,通过学习自动生成贝叶斯网的方法日益受到重视,有一些学习  相似文献   

7.
自动作曲或称算法作曲是利用计算机进行自动或半自动的音乐创作过程。算法作曲的关键之一是生成音高。然而,不确定性是音乐本身固有的特征。贝叶斯网是不确定性知识的表示和推理的典型工具,已经成功应用到很多领域。在MIDI格式的基础上,利用贝叶斯网在算法作曲中生成音高,首先建立一个关于音高的贝叶斯网模型并基于此模型建立知识库。其次,基于贝叶斯网对音高进行推理,生成给定节拍处的每一个音的音高。实验表明,所提出的音高推理方法是可行的。  相似文献   

8.
田翔 《微计算机信息》2007,23(27):253-254,77
作为一种知识推理和进行概率推理的框架,贝叶斯网络在具有内在不确定性和决策问题中得到了广泛的应用。因果推理是态势评估中的一个重要环节,用贝叶斯网找出态势假设和事件之间的潜在关系,正是态势评估所需完成的功能。根据态势与实践之间不同的连接关系建立了态势评估的贝叶斯网络模型,并分别介绍了相应的信息传播算法,最后一个实例来说明该网络的计算过程。  相似文献   

9.
贝叶斯网用一种紧凑的形式表示联合概率分布,具有完备的语义和坚实的理论基础,目前已成为人工智能领域处理不确定性问题的最佳方法之一。贝叶斯网学习是其关键问题,传统学习方法存在如下不足:(1)随节点数增多非法结构以指数级增加,影响学习效率;(2)在等价结构之间进行打分搜索,影响收敛速度;(3)假设每个结构具有相同的先验概率,造成等价类中包含结构越多则先验概率越高。本文提出一种学习马尔科夫等价类算法,该算法基于骨架空间进行状态转换,利用从骨架空间到等价类空间的映 映射关系实现学习贝叶斯网等价类。实验数据证明,该方法可有效缩小搜索空间规模,相对于在有向图空间搜索的算法加快了算法的收敛速度,提高了执行效率。  相似文献   

10.
针对知识图谱中实体间的关联关系存在不确定性、实体间关联度计算复杂度高等问题,提出一种基于贝叶斯网的实体间关联度的计算方法.针对知识图谱做预处理,利用剪枝后获取的核心子图构建贝叶斯网,提出基于知识图谱的贝叶斯网构建方法;利用贝叶斯网作为知识图谱中实体之间关联关系的量化和推理框架,基于贝叶斯网的概率推理,提出知识图谱中实体间关联度的定量计算方法.建立在真实数据之上的实验结果验证了方法的有效性.  相似文献   

11.
Due to the rapid changes in circumstances of cooperates such as globalization, technical innovation and competition, inter-dependence among cooperates which compose supply chain has been intensified. This make cooperates be exposed to various risk and even a small uncertainty can disrupt the balance of whole supply chain. Therefore, in this paper, the framework to develop alternative backorder replenishment plan to minimize the total replenishment cost and expected risk cost has been devised. In order to model the relationship between risks and risk propagation, Bayesian Belief Network has been applied. Moreover, with the fast heuristic algorithm, breath first search and elementary stepwise system based reverse Dijkstra, the alternative backorder replenishment plan can be established. The numerical example shows how to apply the proposed framework and make dynamic backorder replenishment plan considering impact of risk.  相似文献   

12.
The popularity of Bayesian Network modelling of complex domains using expert elicitation has raised questions of how one might validate such a model given that no objective dataset exists for the model. Past attempts at delineating a set of tests for establishing confidence in an entirely expert-elicited model have focused on single types of validity stemming from individual sources of uncertainty within the model. This paper seeks to extend the frameworks proposed by earlier researchers by drawing upon other disciplines where measuring latent variables is also an issue. We demonstrate that even in cases where no data exist at all there is a broad range of validity tests that can be used to establish confidence in the validity of a Bayesian Belief Network.  相似文献   

13.
在这篇论文中,阐述了用贝叶斯信任网络(Bayesian Belief Networks:BBN)进行软件建模的方法,提出了基于BBN软件开发模型,该模型能够表示软件过程的主要活动,给出了如何构建BBN开发模型的步骤,在定义要求控制和计划的关键工作流时该模型能支持专家意见,这种模型能够应对软件开发过程的迭代特性,并对开发过程中的每一步都会渐近产生精确评估,根据其结构可对每一个工作流的整体结果做出评估。  相似文献   

14.
In telecommunication industry, for many organizations, it is really important to take place in the market. As competition increases between companies, customer churn becomes a great issue to deal with by the telecommunication providers. For an effective churn management, companies try to retain their existing customers, instead of acquiring new ones. Previous researches focus on predicting the customers with a propensity to churn in telecommunication industry. In this study, a model is constructed by Bayesian Belief Network to identify the behaviors of customers with a propensity to churn. The data used are collected from one of the telecommunication providers in Turkey. First, as only discrete variables are used in Bayesian Belief Networks, CHAID (Chi-squared Automatic Interaction Detector) algorithm is applied to discretize continuous variables. Then, a causal map as a base of Bayesian Belief Network is brought out via the results of correlation analysis, multicollinearity test and experts’ opinions. According to the results of Bayesian Belief Network, average minutes of calls, average billing amount, the frequency of calls to people from different providers and tariff type are the most important variables that explain customer churn. At the end of the study, three different scenarios that examine the characteristics of the churners are analyzed and promotions are suggested to reduce the churn rate.  相似文献   

15.
传统的CPM和PERT方法难以对项目的进度延迟风险进行准确的定量分析。将专家先验知识与问卷调查数据相结合,建立了建设项目进度风险评估的贝叶斯信念网络模型,采用NETICA软件对样本数据进行拟合,得到了网络模型各节点间的条件概率分布。模型的应用证明该方法能够比较准确地实现对进度延迟风险的定量预测,具有良好的应用前景。  相似文献   

16.
深度信念网络的隐含神经元大部分为噪声变量,且具有组结构相关性。组稀疏深度信念网络模型通过组Lasso模型对隐含神经元变量进行约束,从而实现变量组选择。然而,组稀疏深度信念网络模型未能考虑特征可同时属于多个特征组,并且隐含神经元在变量层面上不稀疏的问题。在组稀疏深度信念网络模型上引入重叠组结构,解释了重叠组Lasso模型在变量层面上比组Lasso模型稀疏的原因,并在变量层面上作进一步的稀疏,提出了重叠稀疏组深度信念网络模型。在MNIST、USPS、ETH-80以及人脸数据集上的识别结果表明,重叠稀疏组深度信念网络具有更高的识别率。  相似文献   

17.
The complexity and spatial heterogeneity of ecosystem processes driving ecosystem service delivery require spatially explicit models that take into account the different parameters affecting those processes. Current attempts to model ecosystem service delivery on a broad, regional scale often depend on indicator-based approaches that are generally not able to fully capture the complexity of ecosystem processes. Moreover, they do not allow quantification of uncertainty on their predictions. In this paper, we discuss a QGIS plug-in which promotes the use of Bayesian belief networks for regional modelling and mapping of ecosystem service delivery and associated uncertainties. Different types of specific Bayesian belief network output maps, delivered by the plug-in, are discussed and their decision support capacities are evaluated. This plug-in, used in combination with firmly developed Bayesian belief networks, has the potential to add value to current spatial ecosystem service accounting methods. The plug-in can also be used in other research domains dealing with spatial data and uncertainty.  相似文献   

18.
The paper proposes an application framework to be used for medicine assisted diagnosis based on ontology and Bayesian Network (DBNO). There are two goals: (1) to separate the domain knowledge from the probabilistic information and (2) to create an intuitive user interface. The framework architecture has three layers: knowledge, uncertainty model and user interface. The contributions of the domain experts are decoupled, the ontology builder will create the domain concepts and relationships focusing on the domain knowledge only. The uncertainty model is Bayesian Network and the probabilities of the variables states are stored in a profile repository. The diagnostician will use the user interface feeded with the domain ontology and one uncertainty profile. The application was tested on a sample medicine model for the diagnose of heart disease.  相似文献   

19.
在因果图理论中,采用了图形化和直接因果强度来表达知识和因果关系,它克服了贝叶斯网的一些不足,已经发展成了一个能够处理离散变量和连续变量的混合模型。但已有的因果图的推理算法还不能完全适应实际问题的需要,这大大地限制了因果图推广和使用,然而信度网研究已比较成熟,已有许多现成的算法和实用的推理软件。文中给出了从因果图向信度网转化的一般方法,包括因果图的连接强度向信度网的条件概率表转化和因果图的结构向信度网的结构转化,从而可以利用信度网的这些成果。  相似文献   

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