CS 4750 HCI

1
User-Centered Design Principles
2
Agenda

• Questions
• Project in detail ThursdayExplore interesting
  user problems off-the-desktop everyday
  activities
• Complete Project Group Design Activity
• User-Centered Design

3
What is HCI?

• What are the 3 Us of HCI and an example of
  each?
• What are 2 of the interaction paradigm shifts and
  one person associated with one of these?
• List 2 design heuristics from DOET and an example
  of each.

4
Complete Design Problem

• Get with your project group
• Select someone to be the User they will get
  participation points
• Other group members form design team
• Design an interactive application for this user
  for the activity/task
• Present design during this class

5
User-Centered Design

• Understand requirements
• similar products
• needs of users
• problems with existing designs
• Develop product

6
Software Development

• From Engineering perspective
• Waterfall Model
• Spiral Model
• W model

Series of activitiesGet all requirements from
userNot a lot of variety
7
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
• A simple interaction design model

8
A simple interaction designmodel
Identify needs/ establish requirements
(Re)Design
Evaluate
Build an interactive version
9
What is Interaction Design?

• It is a process
• a goal-directed problem solving activity informed
  by intended use, target domain, materials, cost,
  and feasibility
• a creative activity
• a decision-making activity to balance trade-offs
• It is a representation
• a plan for development
• a set of alternatives successive elaborations

10
Four basic activities

• There are four basic activities in Interaction
  Design
• 1. Identifying needs and establishing
  requirements
• 2. Developing alternative designs
• 3. Building interactive versions of the designs
• 4. Evaluating designs

11
Three key characteristics

• Three key characteristics permeate these four
  activities
• 1. Focus on users early in the design and
  evaluation of the artefact
• 2. Identify, document and agree specific
  usability and user experience goals
• 3. Iteration is inevitable. Designers never get
  it right first time

12
Who are the users?

• Not as obvious as you think
• those who interact directly with the product
• those who manage direct users
• those who receive output from the product
• those who make the purchasing decision
• those who use competitors products ???
• Three categories of user
• primary frequent hands-on
• secondary occasional or via someone else
• tertiary affected by its introduction, or will
  influence its purchase.
• Wider term stakeholders

13
Who are the users? (contd)

• What are their capabilities? Humans vary in many
  dimensions!
• Some examples are
• size of hands may affect the size and positioning
  of input buttons
• motor abilities may affect the suitability of
  certain input and output devices
• height if designing a physical kiosk
• strength - a childs toy requires little strength
  to operate, but greater strength to change
  batteries

14
What are needs?

• Users rarely know what is possible
• Users cant tell you what they need to help
  them achieve their goals
• Instead, look at existing tasks
• their context
• what information do they require?
• who collaborates to achieve the task?
• why is the task achieved the way it is?
• Envisioned tasks
• can be rooted in existing behaviour
• can be described as future scenarios

15
Understanding users work

• Understanding users work is significant
• Ethnography from anthropology
• writing the culture
• participant observation
• Difficult to use the output of ethnography in
  design

16
Participatory Design

• Scandinavian history
• Emphasises social and organisational aspects
• Based on study, model-building and analysis of
  new and potential future systems

17
Participatory Design (contd.)

• Aspects to user involvement include
• Who will represent the user community?Interaction
  may need to be assisted by a facilitator
• Shared representations
• Co-design using simple tools such as paper or
  video scenarios
• Designers and users communicate about proposed
  designs
• Cooperative evaluation such as assessment of
  prototypes

18
Contextual Design

• Developed to handle data collection and analysis
  from fieldwork for developing a software-based
  product
• Used quite widely commercially
• Contextual Design has seven parts
• Contextual inquiry, Work modeling,
• Consolidation, Work redesign,
• User environment design,
• Mock-up and test with customers,
• Putting it into Practice

19
Contextual Inquiry

• An approach to ethnographic study where user is
  expert, designer is apprentice
• A form of interview, but
• at users workplace (workstation)
• 2 to 3 hours long
• Four main principles
• Context see workplace what happens
• Partnership user and developer collaborate
• Interpretation observations interpreted by user
  and developer together
• Focus project focus to help understand what to
  look for

20
Thursday

• Project discussion in detail
• How can you determine the needs of your users?
  How can you acquire some of the domain knowledge?
  Who are the stakeholders?