Project: Visualization of Causal Relations News (2003-10-17) The slides for our presentation at InfoVis 2003 are now available here. (2003-09-01) We are currently working on adapting the CausalViz codebase to the new Gtk-- library. (2003-06-11) Our work on Growing Polygons, the successor to the Growing Squares technique, has been accepted for presentation at the InfoVis 2003 conference. (2003-06-06) The slides for our presentation at the ACM SoftVis 2003 conference are now available on this website. (2003-01-30) Our paper on CausalViz has been accepted for presentation at the ACM conference for Software Visualization 2003 in San Diego, June 11-13! (2002-11-07) The first public release, CausalViz 0.1.0, has been put up in the download section. (2002-11-07) The schedule for the upcoming usability test has been added to this page. Use this schedule when finding a suitable time. (2002-11-07) A Growing Squares technical report has been added to the list of publications. Introduction The notion of cause and effect is pervasive in human thinking and plays a significant role in our perception of time. The human mind is especially well-suited to detect instances of this concept of causality. For instance, we can all easily trace a rolling billiard ball back to the ball that struck it and set it in motion. However, as the number of actions and reactions in a system grows, it quickly becomes difficult to follow and gain an understanding of its general flow. Accordingly, a billiard table where all 16 balls are moving is impossible to comprehend fully in real-time. Traditional visualizations, notably directed acyclic graphs and Hasse diagrams (also called time-space diagrams, Feynman or Lamport views, see the figure to the right), can allay this problem somewhat, but do not scale well with system complexity and have a high cognitive load due to their fine granularity; users can see the individual relations, but not get a good picture of the system as a whole. To remedy this problem, we are working on the development of novel visualization techniques for causal relations based on animation, colors and patterns to provide an alternate graphical representation of causality in a system that facilitates quick overview. Our investigations penetrate the areas of information visualization, human-computer interaction, and computer graphics (both 2D and 3D). One such visualization technique is the Growing Squares method, were we represent each process (i.e. active entity) in the system as a color-coded square, laid out in a suitable way. We then intuitively ``grow'' each process as time progresses and have the events that causally relate them affect their coloring, somewhat akin to how color pools would spread out on a piece of paper (see the figure to the left). The technique can also be extended to 3D to enhance the visualization with a fixed dimension for the time parameter and at the same time maximize the use of available space (layout efficiency). We have developed a visualization framework, called CausalViz, for causal relations that allows us to compare the Growing Squares method with traditional Hasse diagrams (see the figure to the right). People & Contact Feel free to contact any of the people involved in this project for questions, feedback, praise, and criticism (the e-mail addresses below have been obviously modified to circumvent spambots). Niklas Elmqvist (elm#at#cs.chalmers.se) Philippas Tsigas (tsigas#at#cs.chalmers.se) You may also contact the authors using the following address: Niklas Elmqvist Department of Computing Science Chalmers University of Technology SE-412 96 Goteborg SWEDEN Telephone: +46-31-772 1024 Fax: +46-31-16 56 55 Future Work We aim to improve our existing techniques with extensions and new functionality to make them even more effective. We are also pursuing totally different visualization techniques for causal relations, especially using 3D computer graphics. Publications Below follows a list of publications pertaining to this project. Niklas Elmqvist, Philippas Tsigas. Causality Visualization Using Animated Growing Polygons. In Proceedings of the IEEE Symposium on Information Visualization 2003, pp. 189-196, October 19-21, Seattle. (This paper is copyright (c) 2003 IEEE.) Niklas Elmqvist, Philippas Tsigas. Growing Squares: Animated Visualization of Causal Relations. In Proceedings of ACM 2003 Symposium on Software Visualization 2003, pp. 17-26, June 11-13, San Diego. (This paper is copyright (c) 2003 ACM.) Niklas Elmqvist, Philippas Tsigas. Growing Squares: Animated Visualization of Causal Relations. Technical report CS:2002-04, Chalmers University of Technology, Göteborg (2002). [Superceded by the SoftVis 2003 article.] Download The source code of the CausalViz application is developed under the GNU General Public License (GNU GPL). Below are the releases currently available for download: CausalViz 0.1.0 - initial public release of the CausalViz application. Implements the Growing Squares (both 2D and 3D) and Hasse visualization techniques. Note that this release comes with no documentation or support, use it at your own risk. Feedback may be directed to me. [ Home | Research | Teaching | Courses | Personal ] Updated 2003-11-14 by Niklas Elmqvist (elm#at#cs.chalmers.se).