Design and evaluation

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Design and evaluation

• Victor Kaptelinin
• October 2, 2006

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Outline

• Design
• What is (interaction) design?
• Perspectives on design
• Methods
• Prototypes
• Types of prototypes
• Advantages and disadvantages
• Evaluation
• Paradigms
• Techniques

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Literature

• Löwgren and Stolterman, 1999
• Hackos and Redish, 1998
• Preece et al, 2002

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Design Salen and Zimmerman

• Design is the process by which a designer creates
  a context to be encountered by a participant,
  from which meaning emerges

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Design more definitions

• Design (6b) The process of selecting the means
  and contriving the elements, steps, and
  procedures for producing what will adequately
  satisfy some need
• (Webster New International Dictionary)
• Interaction design refers to the process that is
  arranged within existing resource constraints to
  create, shape, and decide all use-oriented
  qualities (structural, functional, ethical, and
  esthetic) of a digital artifact for one or many
  clients
• (Löwgren and Stolterman, 2004)

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Design and SDLC
design
Early prototype(s)
Formative evaluation
Advanced prototype(s)
Concept
Summative evaluation
Requirement specification
Implementation
Problem identification
Deployment
User studies
Adoption
PRACTICE (real world)
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Methods and perspectives on the designer

• Designer as a black box
• Design is an art methods should stimulate
  creativity
• Designer as a glass box
• Design is an exact science methods should
  provide how to knowledge
• Designer as a self-organizing system
• Design is an art that can be improved by how
  to knowledge

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Selected methods

• Brainstorming (including 635)
• The six thinking hats
• Why-why-why?
• Function analysis
• Main, necessary, desirable, undesirable
• Innovation by boundary shifting
• Future workshops

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Prototypes

• What is a prototype?
• Low-fidelity vs. high-fidelity prototypes
• Prototypes and mock-ups
• Advantages and disadvantages
• Low fidelity, paper and pencil
• Low fidelity, non-interactive, computer-drawn
• Low fidelity, computer-created
• High fidelity
• Why prototypes?
• Building prototypes

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Advantages and disadvantagesLow fidelity (paper
and pencil)

• Advantages
• Low cost
• Fast and easy to create and change
• Require simple tools
• Work well to illustrate concepts and explore
  metaphors
• Everyone can participate in creating
• Seem more changeable and may encourage more
  suggestions
• Disadvantages
• Show only some of the functionality
• May show features that cannot be implemented
• Are destined to be thrown away
• Require a human to simulate the work of IT
• May not be taken seriously

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Advantages and disadvantagesHigh fidelity

• Advantages
• Users can work with them directly
• Look and feel like a final product
• May show what can be implemented in the final
  product
• Can be used by marketing and sales
• Disadvantages
• Expensive
• Time-consuming
• Require knowledge of a prototyping tool
• May raise unrealistic expectations (the product
  is almost ready)

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Why prototype?

• Saves money
• Makes ideas concrete
• Stimulates modifications and alternatives
• Involves users

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Building prototypes

• Deciding where to start
• Building paper prototypes
• Setting up a grid
• Dont feel all the details first
• Make neat copies to show to others
• Prototyping as a team
• What do you need to prepare?
• Participants
• Communication in the team

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Evaluation example
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Evaluation paradigms

• Quick and dirty evaluation
• Usability testing
• Field studies
• Predictive evaluation

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Evaluation techniques

• Observing users
• Asking users
• Asking experts
• Testing users performance
• Modeling users

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The DECIDE framework (Preece et al, 2002)

• Determine goals
• Explore questions
• Choose the paradigm and techniques
• Identify practical issues
• Decide how to deal with ethical issues
• Evaluate, interpret, and present the data