CEN3722 Human Computer Interaction Interface Metaphors and Conceptual Models Dr. Ron Eaglin

Objectives Define and describe how metaphors are used in design Verbal metaphor Virtual metaphor Composite metaphor Define and provide examples of Conceptual Models Design model User’s model System image

Metaphor

Metaphors Used to control complexity Interface actions or tasks mapped to already understood concepts User prior experience and knowledge to help with the novel or unfamiliar Establish user expectations Allow predictions of system behavior

Metaphor Example - Desktop Clipboard Recycle bin Trash File cabinet Calendar Clock Messages Note the mismatch of Windows 8 to the metaphor of the desktop as compared to Mac

Types of Metaphors Verbal metaphor – comparing previous (old) to new technology. Example: Word processor vs. typewriter Virtual metaphor – interface elements with metaphor Example: Desktop adds mouse clicks= selection, drag/drop = move Composite metaphor – add new features to metaphor Example: Add menus to desktop metaphor (new feature) Virtual metaphors provide one:one relationship in metaphor, where composite adds elements that do not exist in base system

Conceptual Models How systems are understood by different people User conceptualize the system Designers conceptualize the system These should be consistent Interfaces communicate the conceptual model Should not need documentation Things should be visible

Design Model User Model User gets model from experience and usage If the models match – ease of use If not user makes mistakes – rejects UI

Summary Define and describe metaphors and use in design Verbal metaphor, virtual interface metaphor, composite metaphor Define and give examples of conceptual models Design model, user model, system image