Models of Interaction - Northeastern University 4300 Lecture...Slips Capture errors start of task...
Transcript of Models of Interaction - Northeastern University 4300 Lecture...Slips Capture errors start of task...
Models of Interaction
Essentially all models are wrong but some are useful.
--George Box
Interaction Frameworks
Benyon examplesNorman: psychopathology of everyday thingsInteraction stylesInteraction paradigmsAffective/Aesthetic/Emotional framework
Benyon
● Early models from cognitive psychology○ Disembodied cognition○ Human Information Processing
● Shortcomings?○ Oversimplified○ No context (examples?)○ Asocial○ No affect, embodiment
Cognitive Psyc Modele.g., SIGCHI Framework....or how I see the world
Distributed Cognition
Cognitive processes and knowledge are often distributed across multiple people, tools andrepresentations.
Examples?
Activity TheoryHuman activity is the unit of analysisDefines aspects (facets)● Subject● Object● Mediating artifacts● Community● Social rules● Division of labor
Activity Theory
“Activity Triangle”for transferring acharacter.
Activity Theory
1. Activities are smallest unit2. Contradictions drive self-organizing activity
systems3. Learning leads to activity changes● Operations● Contradictions
Distributed Cognition● Computation is a medium● Meaning arises on multiple levels● Users, not designers, create and communicate meaning● Users, not designers, manage coupling● Embodied technologies participate in the world they
represent● Embodied interaction turns action into meaning
Example: using a hammer
Distributed Cognition
The Psychopathology of Everyday Things
● What objects do we routinely interact with in our environment?
● Norman: We routinely interact with 10,000-30,000 objects in our environment
● Norman: interested in failures
Norman Chapter 1
● Affordances● Visibility● Conceptual models● Constraints● Mappings● Feedback
Affordances
The fundamental properties of a thing that determine just how it could possibly be used.Examples?
A chair affords sittingKnobs are for turning.Slots for inserting things into.
Visibility
aka “Obviousness”● The correct parts must be visible.● They must convey the correct message.● Impacts learnability.● How different from affordance?Examples?
An Example From Chemistry
Conceptual Model
Mental representation of how a thing works● allows you to mentally simulate and predict
its behavior.
I am not my user
Constraints
Limits the way one users an object.
Mappings
● Relationship between controls and functions.● Natural mapping – taking advantage of
physical analogies and cultural standards – leads to immediate understanding.○ Extreme Form: Skeuomorphism
Feedback
Providing user with information about theresults of an action.1. Immediate control manipulation2. Updated system3. In progress
Feedback Example● Air France Flight 447, 1 June 2009● Stalled, crashed, killed 228 people● Final report:
○ Initial cause: icing of airspeed sensors○ Many feedback problems:
■ Inconsistency with airspeed measurements■ Incomprehension when utopilot disconnected■ The lack of a clear display in the cockpit■ A failure to identify the aural stall warning■ Absence of visual stall information
Norman's Interaction Framework
● domain – the area of work under study ○ e.g. graphic design
● goal – what you want to achieve ○ e.g. create a solid red triangle
● task – how you go about doing it ○ ultimately in terms of operations or actions ○ e.g. … select fill tool, click over triangle
Execution / Evaluation Loopuser establishes the goalformulates intentionspecifies actions at interfaceexecutes actionperceives system stateinterprets system stateevaluates system state with respect to goal
Execution / Evaluation Loopuser establishes the goalformulates intentionspecifies actions at interfaceexecutes actionperceives system stateinterprets system stateevaluates system state with respect to goal
Execution / Evaluation Loopuser establishes the goalformulates intentionspecifies actions at interfaceexecutes actionperceives system stateinterprets system stateevaluates system state with respect to goal
Execution / Evaluation Loopuser establishes the goalformulates intentionspecifies actions at interfaceexecutes actionperceives system stateinterprets system stateevaluates system state with respect to goal
Norman's Interaction Framework
Gulf of executionuser’s formulation of actions!= actions allowed by the system
Gulf of evaluationuser’s expectations about system state!= presentation of state by system
Slip vs. Mistake
SlipError in executing an action
MistakeError in formulating intention & action
Human Errors - slips and mistakesSlip
Understand system and goalCorrect formulation of actionIncorrect action
Mistakemay not even have the right goal
How to Fix These?slip - better interface designmistake - better understanding of system
Norman Ch 5: Design for Errors
● Slips● Mistakes● Modes● Prevent Errors● Error Recovery
Slips● Capture errors
○ start of task sequence same, e.g., drive to store, but go to work● Description errors
○ two tasks are very similar, e.g., throwing laundry in toilet● Data-driven errors
○ need a number, but confronted with another and get confused● Associative activation errors
○ internal associations between tasks, e.g., freudian slips● Loss-of-activation errors
○ forgetting why you started a task● Mode errors
Slips● All caused by inattention● Do confirmation dialogs help?
Mistakes
● “Wide” vs. “Deep” tasks○ Many options, but few steps (e.g. ordering)○ Many steps (driving to work)
● Most everyday tasks are Wide or Deep● Most computer tasks are BOTH
● Do confirmation dialogs help?
Design for Error
● Design to minimize error● Undo● Error Feedback● Attitude: assume errors will be made as part
of problem solving
Forcing Functions
Lockouts
Test: Slip or Mistake?1. A user playing your new Virtual Autopsy game wants to
make an incision but clicks on the MagicMarker tool, thinking it is a scalpel.
2. She finally selects the scalpel but while making the incision (using mouse click-and-drag) her pet cat startles awake and yelps, causing the distracted user to make the cut in the wrong place.
3. The user wants to amputate a limb. Not knowing what tool to use, she randomly selects the scalpel.
Common Interaction Styles
● command line interface● menus● natural language (including speech)● question/answer and query dialogue● form-fills and spreadsheets● WIMPPros & Cons of each?
Initiative
● Who has the initiative?○ Wizard – computer○ WIMP interface – user
● WIMP exceptions …○ pre-emptive parts of the interface○ (Blocking) Modal dialog boxes
■ come and won’t go away!■ good for errors, essential steps■ but use with care
Interaction Paradigms
Batch Processing (initial)
Time Sharing
Networking
Graphical Displays
Microprocessor / Personal Computers
World Wide Web / Cloud Computing
Do we really need an example?
Ubiquitous Computing
Apple -1987 - "Knowledge Navigator"
http://youtu.be/HGYFEI6uLy0
...keeping in mind Bush's Memex
Sixth Sense
http://youtu.be/ZfV4R4x2SK0
What do you think? They loved this at TED.
Announcements for Feb 1
1. Final exam2. Drifting schedule may mean adjusting the
deadlines (hopefully not)
Tangible User Interfaces
http://youtu.be/CUlp30uTw6U (not the best example but OK)
Glass Concept Video
http://youtu.be/JSnB06um5r4
Take-aways
● Norman concepts & interaction framework● Describe different interactive frameworks● Describe and cite 2-3 examples of
○ Interaction styles○ Interaction paradigms○ Affective/Aesthetic/Emotional frameworks (to come)
For Next Class● Read
○ Requirements analysis: Users & Tasks (Benyon Ch 11)
○ Intro to Usability (Benyon Ch 4)○ We will continue interaction models
● Final Project Proposals (next class)● Continue I3 ethnography homework (1 wk)