Transcript How times have changed

Interaction Design
Chapter 4
Overview
 Process in a nutshell
– What is ‘interaction design’?
– Multiple viewpoints
– Outcomes of interaction design
 Main phases
– Understanding users
– Prototyping
– Evaluation
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What is ‘Interaction Design’
 Focus on the interactive elements of the
technology?
 Focus on the human/social processes?
 No:
– About the relationship of the technology and users in
context
– “interspaces” not “interfaces” (Winograd, 1997)
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What is ‘Interaction Design’?
 Three main steps
– Understanding users
– Developing prototypes
– Evaluation
 Highly participative and collaborative
– Stakeholders: user community, industrial designers,
engineers, software developers…
 Highly iterative
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Multiple Viewpoints
 Many techniques and tools
 Many disciplines
 Participation and collaboration
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 Many
techniques
and tools
–
(see Chapter 4, pg114
for full table)
 Role of
triangulation
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Many Disciplines
 Influences needed to shape effective computer systems
have changed over last 50 years (Grudin, 1990)
– 1950s computers like newborn infants
• Adored by engineers and programmers
– 1960s computers like schoolchildren
• Main users were programmers: OS/ programming languages
improved ‘usability’
– 1970s… computers take their place in the adult world
• World full of people with less commitment, time to adapt to
computers. ‘User interface’ coined. Human factors, psychologists,
cognitive scientists.
– 1980s/1990s computers as team players
• Organisational use of computers. Sociologists, anthropologists…
– Current… From the workplace to everyplace
• Industrial design, art, marketing…
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Participation and
Collaboration
 Workers as cogs-in-a-wheel
– Taylorism: “Principles of Scientific Management”
 Scandinavian approach
– Just, participative, cooperative
 Participatory Design methods (Muller, 2001)
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Mobile/Ubicomp PD Method: The Collaboratorium
(Bodker & Buur, 2002)
 Problem:
– Want to envisage ways to improve work practices at
wastewater plants
 Approach
– Participants: engineers, marketers, interaction
designers, workers
– Three activities:
• Design game - board game represented plant, game pieces
different sensors/ displays
• Movie making - act-out one promising innovation
• Critique - show movies, explain rationale
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 Nilsson et
al, 2000
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From Interaction Design to
Deployment
 Blueprint for the new service/ application
– Working prototypes, paper designs, rationales,
background materials etc
– Used by software developers
 Beware ‘translation effects’ and compromises by
implementation team
– Get commitment and input early on
– Communicate the design effectively
– Remain involved
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Main Phases




Understanding Users
Developing Prototype Designs
Evaluation
Will overview now and focus in during other
sessions
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Understanding Users
 A priori knowledge from physiological, psychological and
sociological work
 Field studies
– Rise of ‘ethnography’ based approaches
• “corporate anthropology is now mainstream…” (Economist, 2004)
• Push-to-talk study (Woodruff & Aoki, 2003)
– Lived with participants
– Eavesdropped on conversations
– 50 hrs of recorded, 70,000 word corpus
 Direct questioning
– Field study easier in non mobile applications - backdrop of action
is more stable
– Interviews, focus-groups etc can help validate impressions from
field, fill in gaps when you can’t observe users etc
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Design Exercise:Design for
the Elderly
 What distinct attributes should be accommodated
when designing for this group?
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Developing Prototype Designs
 Design space
– Shaping using guidelines
• High-level: “Design for truly direct manipulation”
• Detailed: “To minimize stylus movement, list commands from
top to bottom in order of expected frequency of use”
(Microsoft, b)
– Managing using design rationale tools etc
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Design Rationale Example
 QOC
(MacLean
et al,
1989)
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Prototyping
 Low-fi vs Hi-fi
– Low-fi do not resemble final products, quick and cheap
to make, evaluate and modify
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Evaluation
 User-centred testing
– Lab-based
• Completion times, accuracy, error rates/ types
• Compare with performance measures or alternative designs
– Ecological validity
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Evaluation
 Performance predictive models
– Example: KSPC model (Mackezie, 2002). Average
number of keystrokes to generate a character.
• KSPC= sum(Kw xFw)/ sum(Cw Fw)
–Kw is keystrokes for a word
–Fw is frequency of word
–Cw is characters in word
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Summary
 Interaction design involves
– Understanding users
– Developing prototypes
– Evaluation and refinement in iterative, participative
fashion
 Range of tools and techniques involved
 Feeds into larger software development
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Reading
 Chapter 4, Mobile Interaction Design
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