Graph data has become increasingly prevalent in data-mining and data analysis generally. Many types of data can be represented naturally as graphs including social network data, log traversal, and online discussions. Moreover recent work on the importance of social relationships, peer tutoring, collaboration, and argumentation has highlighted the importance of relational information in education including: Graphical solution representations such as argument diagrams and concept maps; Graph-based models of problem-solving strategies; User-system interaction data in online courses and open-ended tutors; Sub-communities of learners, peer-tutors and project teams within larger courses; and Class assignments within a larger knowledge space.
McTavish describes a general technique to support graph analysis and visualization particularly for student materials through the use of interactive hierarchical edges. We thank the included authors for their contributions to the discussion and look forward to continued research.