Text input for mobile devices: comparing model prediction to actual performance

ABSTRACT

A study was conducted to obtain performance data for entering text on a mobile phone in order to compare it to performance predictions based on two different mathematical models. Speed data was obtained for two text input methods, T9 Text Input and Multi-tap. While the direction of the results was the same for both the performance data and both model predicitons (with predictive text entry being faster than Multi-tap text entry), the results for all three differed in magnitude. Suggestions for this discrepancy are provided. In addition, in order to help shape future models, additional results are presented for both input methods to show how both accuracy and speed performance varies based on user experience and text subject matter.

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)

Additional Classification:
  C. Computer Systems Organization
  C.5 COMPUTER SYSTEM IMPLEMENTATION
      C.5.3 Microcomputers
          Subjects: Portable devices (e.g., laptops, personal digital assistants)

  H. Information Systems
  H.1 MODELS AND PRINCIPLES
  H.5 INFORMATION INTERFACES AND PRESENTATION (I.7)
      H.5.2 User Interfaces (D.2.2, H.1.2, I.3.6)
          Subjects: Evaluation/methodology

  I. Computing Methodologies
  I.7 DOCUMENT AND TEXT PROCESSING

General Terms:
Design, Human Factors, Management, Measurement, Performance, Reliability, Theory

Keywords:
keypad input, mobile phones, mobile systems, performance modeling, text entry