Interaction design' Course book, parts 23

1
Interaction design.Course book, parts 2-3

• Sep 11, 2007

2
Part II. People and technologies
3
A seven-stage model of action (Norman)
Goal
Evaluation of interpretations
Intention to act
Interpreting the perception
Sequence of actions
Gulf of execution
Gulf of evaluation
Perceiving the state of the world
Execution of the sequence of actions
The world
4
Mental models

• Cognitive representations (e.g, of our
  understanding of a device) that we can run
• Users model, designers model, system image, and
  conceptual design
• Features (Norman)
• incomplete, peoples ability to run them is
  limited, unstable, do not have firm boundaries,
  unscientific (superstitious behavior
  sometimes), parsimonious (people prefer to
  restart a device rather then recover from an
  error)

5
Memory and attention

• STM, LTM
• Recall vs recognition
• Closure
• Attracting attention
• Avoiding interruptions

6
Part III. Activities and contexts of I(S)D
7
Outline

• The process of interaction design
• Requirements
• Envisionment
• Prototyping and evaluation

8
The process of interaction design (Part I, 2.7)

• Establishing needs and requirements
• Conceptual design
• Physical design
• Prototyping
• Evaluation
• (Implementation)

9
Interaction design activities
Evaluation
Interaction design
Early prototype(s) Conceptual design
Advanced prototype(s) Physical design
Concept
Evaluation
Implementation
Needs and requirements
User studies
Deployment
Adoption
Problem
PRACTICE (real world)
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Requirements (outl.)

• About requirements
• Data collection techniques
• Requirement capturing and scenarios

11
About requirements

• What are requirements?
• something the product must do or a quality that
  the product must have (p. 21)
• Requirement specification
• a formal document which contains the
  requirements (p. 211)
• Functional vs. Non-functional requirements
• MoSCoW rules
• Requirements and PD

12
Data collection techniques

• Interviews
• use of scenarios and prototypes
• think aloud (?)
• contextual inquiry (pp. 453-457)
• practical considerations
• Questionnaires
• Cultural probes
• Focus groups
• Observations
• Artifact collection

13
Requirement capturing and scenarios (ch. 8)

• Advantages of scenarios
• Types of scenarios
• user stories
• conceptual scenarios
• concrete scenarios
• use cases
• Documenting scenarios
• Scenario corpus

14
Envisionment (outl.)

• What is envisionment?
• externalizing thoughts, making ideas visible (p.
  233)
• Metaphors
• Representations uses
• Representations types
• Design space analysis
• Steps of the envisionment process

15
Representations uses

• Generation of new ideas
• Accurately expressing ideas
• Testing ideas
• Making predictions

16
Representations types

• Scenarios
• Sketches and snapshots
• Storyboards
• Mood boards
• Navigation maps

17
Design space analysis

• QOC
• Questions
• Options
• Criteria

18
Steps of the envisionment process

• Review requirements and conceptual scenarios
• Develop represenations of your ideas
• (Experiment with different metaphors)
• Involve intended users throughout the processes
• (Explore design decisions)
• Reconsider requirements

19
Prototyping and evaluation (outl.)

• Prototypes
• Lo-fi vs. hi-fi prototypes
• Hi-Fi advantages and disadvantages
• Conceptual vs. physical design
• Evaluation
• General
• Basic evaluation plan
• Expert evaluation
• User evaluation

20
Why prototyping?

• Prototype
• A concrete but partial representation or
  implementation of a system design (p. 253)
• Interactive
• Makes it possible to involve people in evaluating
  design idea

21
Lo-fi vs. hi-fi prototypes

• Low fidelity
• Paper prototypes
• Hi fidelity
• Simulate the look and feel (if not functionality)
  of the anticipated final product

22
Hi-Fi advantages and disadvantages

• Convincing but may lead to premature commitments
• Help answer specific questions but expensive
• Increase validity of user test data but may
  postpone testing
• Enable continuous feedback but may discourage
  radical change suggestions

23
Conceptual vs. physical design (ch. 13)

• Conceptual design
• Creating an abstract description of the system
  its logic, structure, functions, and content
  but not how the structure and functions are to be
  physically realized
• Physical design
• Making concrete decisions about the allocations
  of functions between people and artifacts, how
  the artifacts will look and how they behave
• Designers models, users models, system image
• Interaction patterns

24
Evaluation

• Reviewing, trying out or testing a design, a
  piece of software, or a product to discover
  whether it is learnable, effective, and
  accommodating for its intended user population
  (p. 268)
• Should be used starting from early stages of ID
• Formative vs summative
• A means of involving people

25
Evaluation basic plan

• Establish aims
• Select methods
• Carry out expert reviews
• Plan user testing
• Recruit users and arrange testing
• Carry out user testing
• Analyze results
• (sometimes only ER or UT is used)

26
Expert evaluation

• Heuristics
• Plan
• How many experts?

27
User evaluation

• Intention (aim) Metrics PACT IMPACT
• Basic plan (minimal Cooperative Usability
  Evaluation) (p. 280)
• Data capture techniques
• Reporting the results