Paper Reading #7: Performance optimizations of virtual keyboards for stroke-based text entry on a touch-based tabletop

Swype

Performance optimizations of virtual keyboards for stroke-based text entry on a touch-based tabletop


Jochen Rick


Jochen Rick is an associate professor at Saarland University and is a previous research fellow at The Open University after earning his PhD from Georgia Institute of Technology.


This paper was presented at the UIST '10 Proceedings of the 23rd annual ACM symposium on User interface software and technology.


Summary


In this paper, the researcher explores the validity of the QWERTY keyboard as a viable way to handle input in a touch based world and develops a new model that supports stroke-based input that increases efficiency.


The researcher explains the history of keyboard layouts beginning in 1874 with the QWERTY keyboard after altering a alphabetic design that resulted in keys close together being pressed and jamming the typewriter. Since this keyboard became dominant, many people and companies have tried to improve upon it in both physical and digital environments to no real success.


Next, the researcher creates a model to be used in later steps by performing a study of 8 participants as they perform many tasks, that consist of connecting 4 randomly placed points in a specific order and recording the time it took to go certain distances in certain directions. The stroke was separated into three phases (beginning, middle, end) to further study. The results of the study led the researcher to create a model that is based on a Shannon formulation of Fitts's law.


The researcher then applied this model to the many keyboard designs introduced earlier in the paper and calculated the words per minute rate that could be possible, for stroke-based and tapping input, for each layout. The words used for testing came from the Project Gutenburg library and has shown to be very accurate for these kinds of tests. The results shows the OPTI II and GAG II designs working the fastest while the QWERTY and other more popular layouts performed poorly.


The researcher then applies a simulated annealing process to produce a square-key and hexagon-key layout that result in a faster calculated wpm than the best layouts in the previous analysis.


The researcher concludes by discussing why the QWERTY keyboard has remained a standard for so long despite being shown slower than some other models and explaining that adoption of a new typing layout could prove to be a difficult endeavor but worthwhile as we explore touch.


Discussion


The researcher did achieve his goal of developing an optimized stroke-based keyboard layout for touch input but the real question is does it matter? On this account, I think not because this entire study revolves around tabletop surfaces only which I don't believe will be in common use for the next 5-10 years if even then. It does however point out that keyboard input does need to be fixed for touch based devices.


There is a future in this field for research on a mobile level and in other areas as well. A big segment that this kind of technology would be useful is for disabled people that have to use keyboards such as Swype to track their eye movements and respond in a manner similar to those discussed in this paper. Using an optimized keyboard, this task could be simplified and made quicker.