基于密度聚类的增量动态社区发现算法

现实世界中社交网络中的节点和边随时间动态增加或消失,导致网络中的社区结构也随之发生变化,因此,文中提出基于密度聚类的增量动态社区发现算法.首先,基于改进后的DBSCAN生成初始时刻社区.然后,提出边变化率指标,并结合余弦相似度指标确定相邻时刻邻居发生变化的节点及其邻居节点的社区归属调整.在进行社区归属度计算时,不仅考虑节点直接邻居的影响,还考虑间接邻居的影响.最后,通过迭代更新模块度增益进行社区合并,以减少噪声社区的干扰.在人工数据集和真实数据集上的实验表明,文中算法可以有效应对网络结构突变和增量计算累积误差带来的影响,具有较低的时间复杂度.

Incremental Dynamic Community Detection Algorithm Based on Density Clustering

The community structures of social networks in the real world are always varying with nodes and edges of social networks increasing or disappearing dynamically as time goes by. In this paper, an incremental dynamic community detection algorithm based on density clustering is proposed. Firstly, the initial communities are generated according to the improved DBSCAN algorithm. Then, an index of edge variation rate is proposed and it is combined with the cosine similarity index to determine the community belonging adjustment process of the nodes whose neighbors vary in adjacent moment. In addition, both direct and indirect neighbor nodes are taken into account during the calculation of community belongingness.Finally, the communities are merged by iteratively updating the modularity gain to reduce the interference of noise communities. Experimental results on artificial datasets and real networks show that the proposed algorithm effectively copes with the variation of the network structures and incremental calculation cumulative errors with a low time complexity.