Lifecycle models

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Lifecycle models

1. For more info on these models see text
2. Specific References are in notes view
3. Present the model you think is most appropriate
   for IXD and Web 2.0 processes

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Lifecycle models

• Show how activities are related to each other
• Lifecycle models are
• management tools
• simplified versions of reality
• Many lifecycle models exist, for example
• From software engineering waterfall, spiral,
  JAD/RAD, Microsoft
• from HCI Star, usability engineering

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A simple interaction design model
Identify needs/ establish requirements
(Re)Design
Evaluate
Build an interactive version
Final product
Exemplifies a user-centered design approach
4
Traditional waterfall lifecycle
From software engineering
Requirements analysis
Design
Code
Test
Maintenance
5
Spiral model (Barry Boehm)
From software engineering

• Important features
• Risk analysis
• Prototyping
• Iterative framework so ideas can be checked and
  evaluated
• Explicitly encourages considering alternatives
• Good for large and complex projects but not
  simple ones

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Spiral model (Barry Boehm)
From software engineering
From cctr.umkc.edu/kennethjuwng/spiral.htm
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A Lifecycle for RAD (Rapid Applications
Development)
From software engineering
Project set-up
JAD workshops
Iterative design and build
Engineer and test final prototype
Implementation review
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DSDM lifecycle model
From software engineering
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The Star lifecycle model
From Human Computer Interaction
task/functional analysis
Implementation
Requirements specification
Evaluation
Prototyping
Conceptual/ formal design
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Usability engineering lifecycle model
From Human Computer Interaction

• Reported by Deborah Mayhew
• Important features
• Holistic view of usability engineering
• Provides links to software engineering
  approaches, e.g. OOSE
• Stages of identifying requirements, designing,
  evaluating, prototyping
• Can be scaled down for small projects
• Uses a style guide to capture a set of usability
  goals

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Your Model for AGILE
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Your Model for AGILE IXD