We address the problem of uncertainty quantification for graph-structured data, or, more specifically, the problem to quantify the predictive uncertainty in (semi-supervised) node classification. Key questions in this regard concern the distinction between two different types of uncertainty, aleatoric and epistemic, and how to support uncertainty quantification by leveraging the structural information provided by the graph topology. Challenging assumptions and postulates of state-of-the-art methods, we propose a novel approach that represents (epistemic) uncertainty in terms of mixtures of Dirichlet distributions and refers to the established principle of linear opinion pooling for propagating information between neighbored nodes in the graph. The effectiveness of this approach is demonstrated in a series of experiments on a variety of graph-structured datasets.

图结构数据中对不确定性进行量化，特别是对（半监督）节点分类中的预测不确定性进行量化的问题已被解决。我们提出了一种新的方法，通过利用图拓扑提供的结构信息，用狄利克雷分布的混合物表示（认识论）不确定性，并引用线性观点汇聚的已建立原理，在邻居节点之间传播信息。我们通过一系列实验在各种图结构数据集上展示了这种方法的有效性。

图上线性合并法对不确定性量化