CCT 333: Imagining the Audience in a Wired World

Class 3 : People, Activities, Context and Technologies

Norman’s Principles

• (Continued from last week…see other two in last week notes)

• Constraints

• Mapping

• Consistency

• Affordances

Constraints

• Does the system deliberately constrain the user’s potential?

• Why would you want to constrain certain paths of action?

• Physical, logical and cultural constraints

Mapping

• Does the system mimic existing logical and cultural spatial/temporal relations?

• Problems with arbitrary or random mapping

Consistency

• Does a given action produce similar results every time?

• Is the interface consistent with similar products?

Affordances

• Does the design provide intuitive clues on what can or should be done?

• An overused word?

PACT

• People

• Activities

• Context

• Technologies

• Holistic, interdependent relations among these factors

People

• Or, people come in different shapes and sizes

• User groups are rarely monolithic or homogeneous - often a range of complexity to consider

• Limits can be considered or maintained (and is often done - examples?) but should be done with utmost care

Physical differences

• Height/weight

• Strength and ability differences (coupled with age or training)

• Use of senses

• Physical abilities

Psychological/Social

• Language variety and ability

• Cultural, social and religious custom

• Learning styles (e.g., multiple intelligences)

• Attention and memory

• Mental models

Use Differences

• People of different sizes and backgrounds have different needs

• Novice/experienced users

• Lay/expert users

• Irregular/Regular users

• Organizational/Broad Social contexts - a range of abilities, skills, requirements

Activities

• Or, people of different shapes and sizes need/want to do different things

• Purpose of activity and what enables/constraints it

• Also unintendend purposes and consequences - many of which you want to design against (esp. since people have a tendency to do what they want, not what they need, should or must do…)

Temporal Dimension

• Regular vs. infrequent activity - e.g., twenty times a day vs. once every twenty yrs.

• Time as pressure - does it work when necessary or under acute load?

• Continuous vs. discrete action - one-off action vs. process, and how process is handled

• Response time - does it react reliably as required? Synchronous vs. asynchronous

Cooperation and Complexity

• Solo work or requires cooperation with others (if so, interdependencies and bottlenecks become critical variables)

• Defined vs. vague tasks - defined can be programmed and controlled, vague requires a lot more flexibility

Safety and Error

• Some tasks are mission-critical - failure is not an option

• Handling error and unintended consequence - users behave in mysterious ways (and we shouldn’t be surprised by this…)

• Error and unsafe use - not just user education, but also buy-in

Task and Mediation

• Input methods

• Data structures

• Information Flow

• Output methods

• Feedback

• Not just important in computing - physical examples?

Context

• Or, different people do different things in a range of environments (some of which you can’t easily control)

• Contextual factors may greatly impact people and what tools they use to deal with their tasks - or may be easily predictable and planned for…

Physical Context

• Indoors? Outdoors?

• Mobile? Stationary? (Implications to Access?)

• Loud? Quiet?

• Busy? Still?

• Dangerous? Safe?

Social/Org Contexts

• Access to assistance?

• Social norms of use (and their evolution?)

• Organizational - internal conflict between individual and collective goals? (CSCW examples?)

Technologies

• The things that a range of diverse people use to accomplish an equally diverse range of tasks in particular contexts (getting confusing yet? It should be…)

• Technology broadly defined - realization and formalization of technique (Ellul)

• Design issues similar to #9 and #10 of “activity” section (task and mediation…)

Cui Bono? A slice of healthy skepticism

• Two definitions and its sources• a) figurative/actual - to what good purpose? • b) literal - who benefits?• Technology is rarely the answer to all social

or organizational problems• Esp. in environment of thoughtless

technology hype, asking this question helps.

Design Cycles

• Balancing these (often conflicting) principles is the whole point (and the whole problem

• “There are no rules…and here they are.” (McCloud, 2006)

(Universal?) Elements of Design

• Users and their Requirements

• Conceptual Design

• Physical Design

• Protoyping/Evaluation

• Evaluation and Testing