1. EdgeWrite Cole Gleason
Jacob O. Wobbrock, Brad A. Myers, and John A. Kembel EdgeWrite: a stylus-based text entry method designed for high accuracy and stability of motion. In Proceedings of the 16th annual ACM symposium on User interface software and technology (UIST '03). ACM,  

2. About the Authors Jacob O. Wobbrock Brad A. Myers John A. Kembel
Ph.D. at HCII in 2006
Now at University of Washington
Leads Mobile and Accessible Design Lab
Brad A. Myers
Needs no explanation (I hope!)
Advisor of Jacob
John A. Kembel
MS in HCI from CMU
Design focus

3. Goal of EdgeWrite
People with motor impairments struggle with gestural text entry
Make a text entry method for people with motor impairments:
Stability
Accuracy
Developed at the time when PDAs and Palms were popular
Therefore, compared to Graffiti

4. Problems with Graffiti
Relies on stable, smooth gestures
Segmented input areas
Modal

5. Two Components of Edgewrite
Instead of recognizing a pattern, just look for sequence of corner taps
Physical constraints will result in more:
Stability
Speed
Accuracy
Feedback
Fitts’ Law overshoot

6. Character Set

7. Design of EdgeWrite Path doesn’t matter, only corners. Unistroke
One mode for punctuation only
Capitalization stoke
There are alternate forms too, some users tried these

8. Evaluation (1st Group) 10 users
Between subjects design: Grafitti vs. EdgeWrite
Introduction, practice session, testing session
Realistic entries
Results:
18% improvement in keystrokes per character
Graffiti has faster time per character, but not faster entry overall
Both alphabets very learnable

9. Evaluation (2nd Group) 4 users with motor disabilities
Observation of EdgeWrite with error counts
Results:
Subject 1: Bounce in Grafitti caused punctuation errors
Errors: Graffiti (22/72) and EdgeWrite (68/72)
Subject 2: Could not write some characters
8 errors in Graffiti sentence, none in EdgeWrite
Diagonals were hard
Subject 3: Unable to make some characters in Graffiti, could make them in EdgeWrite
3 errors in Graffiti sentence, none in EdgeWrite
Subject 4: “Much easier, my goodness”
2 errors in Graffiti sentence, none in EdgeWrite

10. Conclusions
Future work on trackballs, joysticks, etc. See other publications!
Questions:
Is EdgeWrite really better than Graffiti for people with and without motor impairments?
Development of assistive technology can lead to products and inventions for people without these impairments as well. What is the role of assistive technology research in technology transfer to industry?
Evaluations of assistive technology tend to be difficult, as authors and you all noted. How does this impact research and development of assistive technology?