Paper Reading #24- Gesture avatar: a technique for operating mobile user interfaces using gestures

Title: Gesture avatar: a technique for operating mobile user interfaces using gestures
Reference Information:
Hao Lu and Yang Li, "Gesture avatar: a technique for operating mobile user interfaces using gestures". CHI '11 Proceedings of the 2011 annual conference on Human factors in computing systems. ACM New York, NY, USA. ©2011. ISBN: 978-1-4503-0228-9.
Author Bios:
Hao Lu- I am a graduate student at University of Washington Computer Science & Engineering and DUB Group. I work on technologies that change and improve the way how people interact with computers.
Yang Li- Yang is a Senior Research Scientist at Google. Before joining Google's research team, Yang was a Research Associate in Computer Science & Engineering at the University of Washington and helped found the DUB (Design:Use:Build), a cross-campus HCI community. He earned a Ph.D. degree in Computer Science from the Chinese Academy of Sciences, and then did a postdoctoral research in EECS at the University of California at Berkeley.
Summary:

• Hypothesis: If using gesture methods to operate mobile interfaces performs optimally over finger-based touch input, then in a dynamic, mobile environment, it will prevail.
• Methods: To correctly and accurately model a user's intent for interaction on a page, the shape of the gesture and the distance from the gesture to the objects aer taken into consideration. After the user draws a gesture, an "avatar" bounding box appears translucently behind the gesture. The user can then interact with that avatar the same way as they would their desired object. Only this avatar is larger than the object on the page so it will be easier to interact with. If the object that gets highlighted is not the desired object, the user may disgard that by using several techniques. The authors conducted a study among 20 participants involving half of them learning gesture avatar and then shift, and vice versa. They were asked to complete tasks using each software. For some tasks, users were sitting down, and for others, they were on a treadmill (to simulate using the device while walking).
• Results: From the study, the authors found that Gesture Avatar was slower than Shift for 20px targets, but faster for 10px targets. Users using Shift while sitting were much faster than while they were walking on the treadmill, but for Gesture Avatar there was no significant difference in time reported. Gesture Avatar's error rates were lower than Shift's for all target sizes. 10 out of the 12 participants preferred using Gesture Avatar over Shift. The authors found that increasing the size of unique characters that would be drawn had no affect on Gesture Avatar's performance. Gesture Avatar supports one-shot interaction and acquiring moving targets also. There have been some integration issues with using Gesture Avatar in existing systems, however.
• Content: The authors wanted to create a way to effectively use your mobile device accurately while in a mobile environment. Touch-activated UIs can be highly inaccurate because of "fat-finger" and "occulation" problems. To correct for these, the authors created a technique to allow the user to "call" a desired object to interact with by "describing it" with a gesture in order for Gesture Avatar to enlarge it so it can be mroe accurately interacted with (and to ensure the correct object is being interacted with). After studies, the authors showed that Gesture Avatar is superior to other similar existing systems.

Discussion:
I thought this was kind of a neat idea. At first, I thought "Oh man, Yang Li is at it with another dumb gesture recognition idea again..." but I was not entirely correct. This time, I believe the proposed system can be extremely useful- especially in a mobile environment. I also liked how the different ways to ensure the correct object is selected is implemented as well. Gesture Avatar allows for disregarding incorrect objects, finding the next best match, interacting more accurately with desired objects, and allowing existing features of a UI to continue to be used if the user didn't want to use Gesture Avatar techniques on a particular page. I might consider using something like this if I did have a smartphone / touch-screen phone. I think Yang and Hao achieved their goals. It always feels good to know something you created out-performs something in existance already.