Text size
  • Small
  • Medium
  • Large
Contrast
  • Standard
  • Blue text on blue
  • High contrast (Yellow text on black)
  • Blue text on beige

    Safer "5-key" number entry user interfaces using Differential Formal Analysis

    HCI2012 - People & Computers XXVI

    Proceedings of HCI 2012
    The 26th BCS Conference on Human Computer Interaction

    Birmingham, UK, 12 - 14 September 2012

    AUTHORS

    Abigail Cauchi, Andy Gimblett, Harold Thimbleby, Paul Curzon & Paolo Masci

    ABSTRACT

    Differential formal analysis is a new user interface analytic evaluation method based on stochastic user simulation. The method is particularly valuable for evaluating safety critical user interfaces, which often have subtle programming issues. The approach starts with the identification of operational design features that define the design space to be explored. Two or more analysts are required to analyse all combinations of design features by simulating keystroke sequences containing keying slip errors. Each simulation produces numerical values that rank the design combinations on the basis of their sensitivity to keying slip errors. A systematic discussion of the simulation results is performed for assessing the causes of any discrepancy, either in numerical values or rankings. The process is iterated until outcomes are agreed upon. In short, the approach combines rigorous simulation of user slip errors with diversity in modelling and analysis methods.

    Although the method can be applied to other types of user interface, it is demonstrated through a case study of 5-key number entry systems, which are a common safety critical user interface style found in many medical infusion pumps and elsewhere. The results uncover critical design issues, and are an important contribution of this paper since the results provide device manufacturers guidelines to update their device firmware to make their devices safer.

    PAPER FORMATS

    PDF filePDF Version of this Paper (1,120kb)