A standard operator in a keystroke-level model (KLM), M represents the act of mentally preparing to execute a command. M is a “catch-all” operator that may include such unobservable actions as making a decision, remembering a procedure or command, visually searching for information, and so on. Because M encompasses all such actions, it is a powerful approximation to human decision making that makes the KLM a relatively easy modeling method to use. M was empirically determined to average 1350 msec by Card, Moran, and Newell (1980b, 1983).
Human-to-human communication may be mediated by technology—for example, by telephone or video phone, by text chat, or by email.
A cognitive structure of concepts and procedures that users refer to when selecting relevant goals, choosing and executing appropriate actions, and understanding what happens when they interact with a computer system (or other tool).
It is a figure of speech in which a word or phrase literally denoting one kind of object or idea is used in place of another to suggest a likeness or analogy between them (defined by Merriam-Webster online dictionary). Designers of graphical user interfaces often use well know objects as interface metaphors to give users an indication of how interface objects will behave. For example, an image of a trash has been adopted to indicate the operation of deleting files.
Notice metaphors can be non-visual, such as in the saying "surfing the web." Here the word surfing is a metaphor.
The “M” in “GOMS,” methods are well-learned sequences of subgoals and operators that can accomplish a goal. There may be more than one method to accomplish a goal. If so, then selection rules are used to determine which method to use in the current task situation.
See model human processor
when an inappropriate system goal is selected and pursued
An simplified expression of reality that is helpful for designing, evaluating, or understanding the behavior of a complex artifact such as a computer system.
model human processor (MHP)
The information-processing cognitive architecture introduced by Card, Moran, and Newell in 1983. It was never realized in a computational form, but it sufficiently specified its memories, processors, communications, and principles of operation that some quantitative predictions of human behavior could be derived. The MHP was merged with GOMS through CPM-GOMS.
MOO (multi-user domain object-oriented)
A MUD in which the characters, their behavior, and all other services are built and extended using an object-oriented programming language.