A Thesis for the degree of Master Korean EdgeWrite: A Korean Text Entry Method for a Joystick Hojin Kim School of Engineering Information and Communications University 2008 i Korean EdgeWrite: A Korean Text Entry Method for a Joystick ii Korean EdgeWrite: A Korean Text Entry Method for a Joystick Advisor: Professor Geehyuk Lee by Hojin Kim School of Engineering Information and Communications University A thesis submitted to the faculty of Information and Communi- cations University in partial fulfillment of the requirements for the degree of Master of Science in the School of Engineering Daejeon, Korea May 13, 2008. Approved by (signed) Professor Geehyuk Lee Major Advisor iii Korean EdgeWrite: A Korean Text Entry Method for a Joystick Hojin Kim We certify that this work has passed the scholastic standards re- quested by the Information and Communications University as a thesis for the degree of Master May 13, 2008 Approved: Chairman of the Committee Geehuk Lee, Associate Professor School of Engineering Committee Member Sung-Hyon Myaeng, Professor School of Engineering Committee Member Jaewoo Ahn, Ph.D., CEO Mobience, Inc. iv M.S. Hojin Kim 20082805 Korean EdgeWrite: A Korean Text Entry Method for a Joystick School of Engineering. 2008, p.50 Major Advisor: Professor Geehyuk Lee Text in English Abstract As advanced features were integrated into joystick-use devices such as video game consoles or portable devices, text entry become an important function. There were some researches about English joystick text entry techniques but, because of the late introduction of the latest joystick-based devices for example PlayStation 3, Korean joystick text entry methods had not been researched ex- cept ASK-HIM which was our former research. We introduced Korean Edge- Write, a Korean text entry method for a joystick. To achieve efficiency and easi- ness, the initial gesture was designed with the analysis of Hangeul; the initial design was modified by a pilot test. The Korean EdgeWrite gesture design was enhanced again after applying participants‟ gesture design from the guessability test. Keystrokes per character for the Korean EdgeWrite could be comparable with that of multi-tap. Immediate usability test showed the Korean EdgeWrite was similarly easy to remember for novice compared to the EdgeWrite or Graffi- ti. In a user study, most of the participants could learn the Korean EdgeWrite i gestures within no longer than 10 minutes. They could enter the text faster using the Korean EdgeWrite than using an alphabetic selection keyboard or a multi-tap selection keypad. Also, the performance shown by a group of well trained users could be comparable with that of a mobile phone keypad. In a post-test survey, the participants gave a higher rating to the Korean EdgeWrite than to the selec- tion-based text entry methods in terms of the preference and the speed. The Ko- rean EdgeWrite outperformed ASK-HIM, another non-selection-based joystick text entry method in Korean, too. ii Contents A Thesis for the degree of Master ....................................................................... i Abstract ................................................................................................................. i Contents ............................................................................................................... iii List of Tables ....................................................................................................... vi List of Figures .................................................................................................... vii List of Abbreviations .......................................................................................... ix I Introduction .................................................................................................. 1 1.1 Motivation ................................................................................................ 1 1.2 Proposed Method ..................................................................................... 2 1.3 Thesis Organization ................................................................................. 2 II Related Work ................................................................................................ 4 2.1 English Joystick Text Entry Method ........................................................ 4 2.2 Korean Joystick Text Entry Method ........................................................ 7 2.3 Text Entry Evaluation .............................................................................. 7 III Korean EdgeWrite ........................................................................................ 9 3.1 Background .............................................................................................. 9 3.2 Core Concepts ........................................................................................ 10 3.3 Goal ........................................................................................................ 10 3.4 Design Procedure ................................................................................... 10 3.5 Korean EdgeWrite Design ..................................................................... 11 3.6 Keystrokes per Character Calculation.................................................... 13 3.7 Guessability ............................................................................................ 14 3.7.1 Background .............................................................................................14 iii 3.7.2 Method ....................................................................................................15 3.7.3 Results ....................................................................................................16 3.7.4 Maximizing Guessability ........................................................................18 3.8 Immediate Usability ............................................................................... 19 3.8.1 Background .............................................................................................19 3.8.2 Method ....................................................................................................20 3.8.3 Results ....................................................................................................22 IV Evaluation.................................................................................................... 24 4.1 Competitor Methods .............................................................................. 24 4.1.1 Alphabetic Selection Keyboard ..............................................................25 4.1.2 Multi-tap 3x4 Selection Keypad .............................................................26 4.2 Method ................................................................................................... 27 4.2.1 Subjects ...................................................................................................27 4.2.2 Apparatus ................................................................................................27 4.2.3 Procedure ................................................................................................28 4.2.4 Measure ..................................................................................................28 4.3 Results .................................................................................................... 29 4.3.1 Speed ......................................................................................................29 4.3.2 Error Rates ..............................................................................................29 4.3.3 Questionnaire ..........................................................................................30 4.4 Well-trained User Evaluation ................................................................. 32 4.5 Comparison with ASK-HIM .................................................................. 33 V Conclusions.................................................................................................. 35 5.1 Thesis Summary ..................................................................................... 35 5.2 Discussion .............................................................................................. 35 5.3 Goal Achievement .................................................................................. 37 iv 5.4 Future Work ........................................................................................... 37 5.5 Final Remarks ........................................................................................ 39 Appendix A Korean EdgeWrite Character Set ......................................... 40 국문요약 ............................................................................................................. 43 References .......................................................................................................... 45 Acknowledgements ............................................................................................ 48 Curriculum Vitae ............................................................................................... 49 v List of Tables Table 1. Guessability results (%). ........................................................................ 17 Table 2. Evaluation results. ................................................................................. 31 vi List of Figures Figure 1. Sony PlayStation Portable Web browser screenshot with Wikipeia Web page.