ChordLink: A New Hybrid Visualization Model

• Published in: Graph Drawing and Network Visualization Vol. 11904; pp. 276 - 290
• Main Authors: Angori, Lorenzo, Didimo, Walter, Montecchiani, Fabrizio, Pagliuca, Daniele, Tappini, Alessandra
• Format: Book Chapter
• Language: English
• Published: Switzerland Springer International Publishing AG 2019; Springer International Publishing
• Series: Lecture Notes in Computer Science
• ISBN: 3030358011; 9783030358013
• ISSN: 0302-9743; 1611-3349
• DOI: 10.1007/978-3-030-35802-0_22

Many real-world networks are globally sparse but locally dense. Typical examples are social networks, biological networks, and information networks. This double structural nature makes it difficult to adopt a homogeneous visualization model that clearly conveys an overview of the network and the internal structure of its communities at the same time. As a consequence, the use of hybrid visualizations has been proposed. For instance, NodeTrix combines node-link and matrix-based representations (Henry et al., 2007). In this paper we describe ChordLink, a hybrid visualization model that embeds chord diagrams, used to represent dense subgraphs, into a node-link diagram, which shows the global network structure. The visualization is intuitive and makes it possible to interactively highlight the structure of a community while keeping the rest of the layout stable. We discuss the intriguing algorithmic challenges behind the ChordLink model, present a prototype system, and illustrate case studies on real-world networks.