Semi-supervised hierarchical clustering via low-density separation
摘要
Semi-supervised clustering (SSC) has received increasing attention in various real-world tasks. Typically, SSC relies on labeled data to supervise the clustering process. However, noisy or insufficient labeled data can mislead clustering or limit the ability to identify optimal solutions. To address these issues, this paper presents an adjusted compact-cluster assumption and thereby proposes a density-based semi-supervised hierarchical clustering (DBSSHC) method which aims to group data into a number of compact clusters. Both labeled data and density variations within clusters are employed to assess the compactness of clusters and guide the top-down clustering process. Especially, a density-based local clustering algorithm is proposed to identify low-density separations and further split uncompact clusters. In summary, this paper proposes a novel SSC algorithm by combining hierarchical clustering and density-based clustering. It not only compensates the deficiency of labeled data but also decreases the impact of noise among labeled data. The proposed method is validated on a variety of benchmark datasets. Measured by NMI, Rn, Accuracy, and Purity, DBSSHC achieves significant superiority over other state-of-the-art SSC methods and yields the best results on more datasets. These experimental results demonstrate the effectiveness of the proposed method. The source code of DBSSHC is available at https://codeocean.com/capsule/9190794/tree.