Bayesian networks are widely used to learn and reason about the dependence structure of discrete variables. However, they are only capable of formally encoding symmetric conditional independence, which in practice is often too strict to hold. Asymmetry-labeled DAGs have been recently proposed to both extend the class of Bayesian networks by relaxing the symmetric assumption of independence and denote the type of dependence existing between the variables of interest. Here, we introduce novel structural learning algorithms for this class of models which, whilst being efficient, allow for a straightforward interpretation of the underlying dependence structure. A comprehensive computational study highlights the efficiency of the algorithms. A real-world data application using data from the Fear of COVID-19 Scale collected in Italy showcases their use in practice.
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已经定义了几种分期树模型的结构学习算法,这是贝叶斯网络的不对称扩展。但是,随着变量考虑的增加数量,它们不会有效地扩展。在这里,我们介绍了第一个针对分阶段树的可扩展结构学习算法,该算法在仅少量依赖项的模型中进行搜索。一项仿真研究以及现实世界的应用程序说明了我们的日常工作以及此类学习的分阶段的实际使用。
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分类的生成模型使用类变量的联合概率分布和功能来构建决策规则。在生成模型中,贝叶斯网络和天真的贝叶斯分类器是最常用的,并提供了所有变量之间关系的明确图形表示。但是,这些具有高度限制可能存在的关系类型的缺点,而不允许特定于上下文的独立性。在这里,我们介绍了一种新的生成分类器类别,称为“分阶性树分类器”,该分类器正式解释了特定于上下文的独立性。它们是通过对事件树的顶点的分区进行构建的,可以正式读取条件独立性。还定义了天真的阶段树分类器,它扩展了经典的天真贝叶斯分类器,同时保持相同的复杂性。一项广泛的仿真研究表明,分级树分类器的分类精度与最先进的分类器的分类精度具有竞争力,并且一个示例展示了它们在实践中的使用。
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