© Springer-Verlag Berlin Heidelberg 2001.Systematic user errors commonly occur in the use of interactive systems. We describe a formal reusable user model implemented in higherorder logic that can be used for machine-assisted reasoning about user errors. The core of this model is a series of non-deterministic guarded temporal rules. We consider how this approach allows errors of various specific kinds to be detected and so avoided by proving a single theorem about an interactive system. We illustrate the approach using a simple case study.
['Paul Curzon', 'A Blandford']
Detecting multiple classes of user errors