Multilingual Touchscreen Keyboard Design and Optimization

A keyboard design, once adopted, tends to have a longlasting and worldwide impact on daily user experience. There is a substantial body of research on touch-screen stylus keyboard optimization. Most of it has focused on English only. Applying rigorous mathematical optimization methods and addressing diacritic character design issues, this article expands this body of work to French, Spanish, German, and Chinese. More important and counter to the intuition that optimization by nature is necessarily specific to each language, this article demonstrates that it is possible to find common layouts that are highly optimized across multiple languages for stylus (or single finger) typing. We first obtained a layout that is highly optimized for both English and French input. We then obtained a layout that is optimized for English, French, Spanish, German, and Chinese pinyin simultaneously, reducing its stylus travel distance to about half of QWERTY's for all of the five languages. In comparison to QWERTY's 3.31, 3.51, 3.7, 3.26, and 3.85 keys of movement for English, French, Spanish, German, and Chinese, respectively, the optimized multilingual layout has an average travel distance of 1.88, 1.86, 1.91, 1.77, and 1.68 keys, correspondingly. Applying Fitts's law with parameters validated by a word tapping experiment, we show that these multilingual keyboards also significantly reduce text input time for multiple languages over the standard QWERTY for experienced users. In comparison to layouts individually optimized for each language, which are also obtained in this article, simultaneously optimizing for multiple languages caused only a minor performance degradation for each language. This surprising result could help to reduce the burden of multilingual users having to switch and learn new layouts for different languages. In addition, we also present and analyze multiple ways of incorporating diacritic characters on multilingual keyboards. Taken together, the present work provides a quantitative foundation for the understanding and designing of multilingual touch-screen keyboards.

[1]  Keisuke Nakano,et al.  Computing the Cost of Typechecking of Composition of Macro Tree Transducers , 2009 .

[2]  Shumin Zhai,et al.  Performance Optimization of Virtual Keyboards , 2002, Hum. Comput. Interact..

[3]  T. Landauer,et al.  Handbook of Human-Computer Interaction , 1997 .

[4]  Dominic J. D. Hughes,et al.  Empirical bi - action tables: A tool for the evaluation and optimization of text input systems , 2002 .

[5]  P. Fitts.  The information capacity of the human motor system in controlling the amplitude of movement. , 1954, Journal of experimental psychology.

[6]  James R. Lewis,et al.  Keys and Keyboards , 1997 .

[7]  Barbara F. Grimes.  Ethnologue Languages of the World , 1988 .

[8]  I. Scott MacKenzie,et al.  Theoretical upper and lower bounds on typing speed using a stylus and a soft keyboard , 1995, Behav. Inf. Technol..

[9]  Shumin Zhai,et al.  Shorthand writing on stylus keyboard , 2003, CHI '03.

[10]  Shumin Zhai,et al.  SHARK2: a large vocabulary shorthand writing system for pen-based computers , 2004, UIST '04.

[11]  Poika Isokoski.  Performance of menu-augmented soft keyboards , 2004, CHI '04.

[12]  Shumin Zhai,et al.  CHAPTER 7 – Introduction to Shape Writing , 2007 .

[13]  James R. Lewis,et al.  Development of a Digram-Based Typing Key Layout for Single-Finger/Stylus Input , 1999 .

[14]  Shumin Zhai,et al.  Chinese input with keyboard and eye-tracking: an anatomical study , 2001, CHI.

[15]  Shumin Zhai,et al.  Movement model, hits distribution and learning in virtual keyboarding , 2002, CHI.

[16]  I. Scott MacKenzie,et al.  The design and evaluation of a high-performance soft keyboard , 1999, CHI '99.

[17]  Jakob Nielsen,et al.  International users interface , 1996 .

[18]  Ben Shneiderman,et al.  Universal Usability , 2000, UBIQ.

[19]  Shumin Zhai,et al.  Interlaced QWERTY: accommodating ease of visual search and input flexibility in shape writing , 2008, CHI.

[20]  Shumin Zhai,et al.  Characterizing computer input with Fitts' law parameters-the information and non-information aspects of pointing , 2004, Int. J. Hum. Comput. Stud..

[21]  Mauro Dell'Amico,et al.  The single-finger keyboard layout problem , 2009, Comput. Oper. Res..

[22]  Dominic J. D. Hughes,et al.  Empirical Bi-Action Tables: A Tool for the Evaluation and Optimization of Text-Input Systems. Application I: Stylus Keyboards , 2002, Hum. Comput. Interact..

[23]  James R. Lewis,et al.  Evaluation of Typing Key Layouts for Stylus Input , 1999 .

[24]  Shumin Zhai,et al.  The metropolis keyboard - an exploration of quantitative techniques for virtual keyboard design , 2000, UIST '00.

[25]  Kumiko Tanaka-Ishii,et al.  Text Entry Systems: Mobility, Accessibility, Universality , 2007 .

[26]  P. Lewis.  Ethnologue : languages of the world , 2009 .

[27]  Shumin Zhai,et al.  Relaxing stylus typing precision by geometric pattern matching , 2005, IUI.