The KLM-GOMS model is designed to be as straightforward as possible. The usersequence of operations is supposedmodeled toas bea thesequence mostof experienceda insmall number of operations. Each operation is assigned a duration, which is orderintended to seemodel the minimalaverage amount of time requiredan forexperienced auser would take to specificperform taskit.
The sequence of operations is minimized to a default set with a specific (medium) time associated to each one.
Kieras (1993, 2001) defines the following operations:
Line 18 ⟶ 16:
* '''W(t)''', wait time (system) - t msec
Note that aA mouse click iswould '''be written "BB'''" (button press, button release) while a sequence of keys is '''"KKK...'''" or '''"T(n)'''" ("T" stands for '"type'").
For example aA common operation that involves pointing and clicking something on the screen iswould expressedbe as:written "MPBB" (think, point, press, release).
ThisWhile test can't be taken obviously asnot the only onetechnique tofor doevaluating to evaluate an interfaceinterefaces, but it'scan usefulbe asused ato complementcompare andthe tospeed compareof two different interfaces designed to performaccomplish the same task.
