ChordLink: A New Hybrid Visualization Model
This addresses visualization problems for researchers and practitioners working with complex networks like social or biological systems, though it is incremental as it builds on existing hybrid approaches.
The paper tackles the challenge of visualizing networks that are globally sparse but locally dense by introducing ChordLink, a hybrid model that embeds chord diagrams for dense subgraphs into a node-link diagram for global structure, enabling interactive highlighting of communities while maintaining layout stability.
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.