Indented Pixel Tree Plots

  • Michael Burch
  • Michael Raschke
  • Daniel Weiskopf
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6453)


We introduce Indented Pixel Tree Plots (IPTPs): a novel pixel-based visualization technique for depicting large hierarchies. It is inspired by the visual metaphor of indented outlines, omnipresent in graphical file browsers and pretty printing of source code. Inner vertices are represented as vertically arranged lines and leaf groups as horizontally arranged lines. A recursive layout algorithm places parent nodes to the left side of their underlying tree structure and leaves of each subtree grouped to the rightmost position. Edges are represented only implicitly by the vertically and horizontally aligned structure of the plot, leading to a sparse and redundant-free visual representation. We conducted a user study with 30 subjects in that we compared IPTPs and node-link diagrams as a within-subjects variable. The study indicates that working with IPTPs can be learned in less than 10 minutes. Moreover, IPTPs are as effective as node-link diagrams for accuracy and completion time for three typical tasks; participants generally preferred IPTPs. We demonstrate the usefulness of IPTPs by understanding hierarchical features of huge trees such as the NCBI taxonomy with more than 300,000 nodes.


Completion Time Leaf Node User Study Visualization Technique Dataset Size 
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  1. 1.
    Tufte, E.R.: The Visual Display of Quantitative Information, 1st edn. Graphics Press, Cheshire (1983)Google Scholar
  2. 2.
    Engelbart, D.C., English, W.K.: A Research Center for Augmenting Human Intellect. Video of Public Demonstration of NLS (1968),
  3. 3.
    McGuffin, M.J., Robert, J.M.: Quantifying the space-efficiency of 2D graphical representations of trees. Information Visualization (2009), doi:10.1057/ivs.2009.4Google Scholar
  4. 4.
    Battista, G.D., Eades, P., Tamassia, R., Tollis, I.G.: Graph Drawing: Algorithms for the Visualization of Graphs. Prentice Hall, Upper Saddle River (1999)zbMATHGoogle Scholar
  5. 5.
    Herman, I., Melançon, G., Marshall, M.S.: Graph visualization and navigation in information visualization: A survey. IEEE Transaction on Visualization and Computer Graphics 6, 24–43 (2000)CrossRefGoogle Scholar
  6. 6.
    Reingold, E.M., Tilford, J.S.: Tidier drawings of trees. IEEE Transactions on Software Engineering 7, 223–228 (1981)CrossRefGoogle Scholar
  7. 7.
    Eades, P.: Drawing free trees. Bulletin of the Institute for Combinatorics and its Applications 5, 10–36 (1992)MathSciNetzbMATHGoogle Scholar
  8. 8.
    Cleveland, W.S., McGill, R.: An experiment in graphical perception. International Journal of Man-Machine Studies 25, 491–501 (1986)CrossRefGoogle Scholar
  9. 9.
    Grivet, S., Auber, D., Domenger, J.P., Melançon, G.: Bubble tree drawing algorithm. In: Wojciechowski, K., Smolka, B., Palus, H., Kozera, R.S., Skarbek, W., Noakes, L. (eds.) Computer Vision and Graphics, Dordrecht, The Netherlands, pp. 633–641. Springer, Heidelberg (2006)CrossRefGoogle Scholar
  10. 10.
    Shneiderman, B.: Tree visualization with tree-maps: 2-d space-filling approach. ACM Transactions on Graphics 11, 92–99 (1992)CrossRefzbMATHGoogle Scholar
  11. 11.
    Andrews, K., Heidegger, H.: Information slices: Visualising and exploring large hierarchies using cascading, semi-circular discs. In: Proceedings of the IEEE Information Visualization Symposium, Late Breaking Hot Topics, pp. 9–12 (1998)Google Scholar
  12. 12.
    Stasko, J.T., Zhang, E.: Focus+context display and navigation techniques for enhancing radial, space-filling hierarchy visualizations. In: Proceedings of the IEEE Symposium on Information Visualization, pp. 57–66 (2000)Google Scholar
  13. 13.
    Yang, J., Ward, M.O., Rundensteiner, E.A., Patro, A.: InterRing: a visual interface for navigating and manipulating hierarchies. Information Visualization 2, 16–30 (2003)CrossRefGoogle Scholar
  14. 14.
    Andrews, K., Kasanicka, J.: A comparative study of four hierarchy browsers using the hierarchical visualisation testing environment. In: Proceedings of Information Visualization, pp. 81–86 (2007)Google Scholar
  15. 15.
    Benson, D.A., Karsch-Mizrachi, I., Lipman, D.J., Ostell, J., Sayers, E.W.: Genbank. Nucleic Acids Research 37, 26–31 (2009)CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Michael Burch
    • 1
  • Michael Raschke
    • 1
  • Daniel Weiskopf
    • 1
  1. 1.VISUS, University of StuttgartGermany

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