One approach to reducing the costs of usability testing is to facilitate the automatic detection of critical incidents: serious breakdowns in interaction that stand out during software use. This research evaluates the use of undo and erase events as indicators of critical incidents in Google SketchUp (a 3D-modeling application), measuring an indicator's usefulness by the numbers and types of usability problems discovered. We compared problems identified using undo and erase events to problems identified using the user-reported critical incident technique [Hartson and Castillo 1998 ]. In a within-subjects experiment with 35 participants, undo and erase episodes together revealed over 90% of the problems rated as severe, several of which would not have been discovered by self-report alone. Moreover, problems found by all three methods were rated as significantly more severe than those identified by only a subset of methods. These results suggest that undo and erase events will serve as useful complements to userreported critical incidents for low cost usability evaluation of creation-oriented applications like SketchUp.
In this space, David Akers et al. REF have recently demonstrated that invocations of the undo and erase commands in 3D modelling software can serve as indicators of usability problems.
Undo and erase events as indicators of usability problems
CHI
Computer Science