"Effective and Efficient Techniques for Hierarchy Interactions"
by Shengdong ZHAO

Abstract

Hierarchies (or trees) are a fundamental organizing structure in the modern information society. It's difficult to visualize a large hierarchy effectively in a given space. Showing the structure is space consuming, and the exponential growth in the number of nodes from the root to the leaves creates difficulties for laying out the items of large hierarchies effectively. Smaller hierarchies, such as hierarchical menus, face a different set of challenges. Since they are used so frequently, more efficient user interactions with menus can lead to major productivity gains as workers focus more on performing the task and less on the problem of selecting associated menu items.

This talk will describe research and evaluation of innovative interaction and selection methods for hierarchies. A method is first introduced for visualizing relatively large hierarchies called Elastic Hierarchies. This method combines the space-efficiency of Treemaps with the structural clarity of node-link diagrams. The remainder of the talk considers the special problem of eyes-free hierarchical menu access in mobile contexts. A new method of mobile menu selection called earPod using touch input and interruptible spatialized audio feedback is introduced. Research results are presented that show that this eyes-free earPod style of interaction compares favorably with the standard iPod menu selection method.  Further results are presented concerning the effectiveness of earPod menu selection during (simulated) driving. The talk will conclude with presentation of some design guidelines derived from this research along with a consideration of the implications of these findings for future research.

About the speaker

Shengdong ZHAO is a Ph.D. candidate in Computer Science at the University of Toronto. He has a Masters degree in Information Management & Systems from the University of California at Berkeley. He is affiliated with the Interactive Media Lab and the Dynamic Graphics Project Lab at the University of Toronto. His advisor is Professor Mark Chignell. Shengdong has pursued a number of projects in Human Computer Interaction, with an emphasis on mobile eyes-free interfaces, gesture input, and information visualization. His Ph.D. dissertation research focuses on the design and evaluation of earPod , an eyes-free menu selection technique, in a variety of user scenarios. He has carried out two research internships at Microsoft Research in Redmond, where he designed and implemented the Zone and Polygon Menus and explored the initial ideas and assembled first prototype for the InkSeine application. InkSeine is now available for public download, and has received reviews as a great TabletPC application from GottaBeMobile.com. Shengdong has co-authored four patent applications. He is currently doing collaborative research with the IBM Almaden Research Center, with Drexel University, and with the National Federation of the Blind on projects relating to his dissertation research.