Comparing the immediate usability of graffiti 2 and virtual keyboard

ABSTRACT

This paper presents the results of an empirical study on the input system of the most frequent PDA operating system, PalmOS from Palm Inc. In an experiment with novice users we compared the stroke based alphabet Graffiti 2 with the Virtual Keyboard and the predictive add-on WordComplete from CIC Software for Graffiti 2. We found that although text input with Graffiti 2 was significantly slower and generated a higher error rate (9 wpm; 19%) than text input with the Virtual Keyboard (13 wpm; 4%), there was no significant difference in usability and task load rating. WordComplete for Graffiti 2 had no significant impact on performance but enhanced user comfort.

REFERENCES

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INDEX TERMS

Primary Classification:
  H. Information Systems
  H.5 INFORMATION INTERFACES AND PRESENTATION (I.7)
      H.5.2 User Interfaces (D.2.2, H.1.2, I.3.6)
          Subjects: Input devices and strategies (e.g., mouse, touchscreen)

General Terms:
Human Factors, Measurement, Performance

Keywords:
WordComplete, graffiti 2, mobile computing, pen-based computing, stylus input, virtual keyboard