Interaction Design
Chapter 10
The Human Action Cycle
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Psychological model
Describes steps users take to interact with
computer systems
Use actions and tasks to achieve goals
The Human Action Cycle
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Goal Formation
Execution stage
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Translate goals into tasks
Planning the action sequence
Executing action sequence
Evaluation stage
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Perceiving what's happening
Interpreting the outcome as per expectations
Comparing what happened with what was wanted
Human Action Cycle
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Can be quick or fast
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Can be broken down into smaller Human
action cycles
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Flexible
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Differs from person to person
Goal Formation
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One step
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Think of a goal
Execution Stage
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Involves thinking and action
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Thinking
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Translate goals into tasks
Planning the action sequence
Action
–
Executing action sequence
Evaluation stage
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All thinking
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Comparing expectation with result
HAC Influence on the Design Process
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Predict difficulties
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Changes to environment and technology
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Skills and training
Explaining the System to the User
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The user has to understand the UI
The user uses
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Prior knowledge
Documentation
Training
We use
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Designer and User model, and the System image
Designer Model
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What the designer knows
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Structural and operational
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Complete and clear
User Model
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What the user knows
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Functional
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Sometimes incorrect
System Image
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Communicate design to user
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Contains
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UI
Documentation
Training
What the user knows
UI and the User
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Needs to meet the user model’s expectation
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Needs to meet the functionality of the
designer model
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Take into account older user models
Metaphor
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Technically all computer UI’s
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Used to make an accurate user model
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Used to unify UI
Problem’s with Metaphors
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Adhering too strictly
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Outside user experience
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Make sure all metaphors connect
Making a metaphor
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Task scenarios, use cases, requirements
gathering
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Make sure makes sense to user
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Make several
Questions?