The prediction would have to be derived from some declaration of the
task frequencies, but the description of the interface would emerge from the
process of designing the interface. A measure of layout appropriateness (frequently used pairs of widgets should be adjacent, and the left-to-right sequence
should be in harmony with the task-sequence description) would also be produced to guide the designer in a possible redesign. Estimates of the perceptual
and cognitive complexity plus the motor load would be generated automatically (Sears, 1992).