SIMS 213: User Interface Design

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SIMS 213 User Interface Design Development

• Marti Hearst
• Thurs, Jan 29, 2004

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Discussion

• Kent Sullivan, The Windows 95 User Interface A
  Case Study in Usability Engineering, CHI 1996.
• A case study of the iterative design process.

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Sullivan Case Study

• 12 people on the Windows 95 team!!
• Waterfall design method (compartmentalized UI
  done at the end during quality assurance stage)
  would produce an unusable product.
• Method
• Find most common tasks, and test on those
• Compare to a baseline (Windows 3.1)
• Rapid prototyping tools
• Importance of usability testing!!
• Stepping back
• Found big problems
• Held a retreat to radically re-think things

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Sullivan Case Study

• Decided to
• Focus on scaffolding (beginner -gt
  intermediate-expert)
• Give up on too much backwards-compatibility with
  3.1
• Dump the huge design spec (!) Encouraged social
  interaction.
• Continually informed outsiders as well as team
  members about the design
• Fine tuning with usablity tests
• Holistic interface test in the lab
• Many participants!
• Longitudinal field study
• About Windows 3.1
• a good demonstration of what happens when
  usability is not taken into account

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Readings for This and Next Lecture

• Cooper (Inmates, Chs. 9-11)
• Constantine Lockwood Ch. 5
• Newman Landay article

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Why User-Centered Design?

• System will fail if it
• does not do what the user needs
• is inappropriate for the user
• Why dont we just define what a good interface
  is?
• There is a huge variety of users and tasks
• Guidelines are usually too vague
• e.g. Provide feedback, Be intuitive

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Participatory Design

• A subset of user-centered design
• User actively participates in design of the
  system
• Pros
• potentially more accurate information about the
  tasks
• more opportunity for users to influence the
  design decisions
• buy-in from sense of participation
• potential greater acceptance of final system

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Participatory Design

• Cons (potential)
• more costly
• lengthier implementation period
• antagonism from those whose suggestion are not
  incorporated
• force designers to compromise design
• exacerbate personality conflicts between
  designers and users
• highlight organizational politics

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User-Centered Design Overview

• Needs assessment
• Find out
• who users are
• what their goals are
• what tasks they need to perform
• Task Analysis
• Characterize what steps users need to take
• Create scenarios of actual use
• Decide which users and tasks to support
• Design based on this
• Evaluation
• Test interface by walking through tasks
• Do this before implementation

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Caveats

• Politics
• advocating change can cause controversy
• get a sense of the organization
• important to get buy-in from all those involved
• Dont design forever without prototyping
• rapid prototyping, evaluation, iteration is key
  to technique
• Systems level apps are poor candidates
• networking, etc.

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Example Student Course EnrollmentHow to Help
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Help Users Achieve Goals

• Example Course Enrollment Software
• What matters from the programmers point of view?
• What matters from users point of view?
• What about the course administrators?

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User-Centered Design Example

• You have been hired by Pizzas R Us (PRU)
• Design a system to
• make online orders from the web
• Also considering special features
• online discount coupons
• allowing party orders in advance
• customer recommendations, linking to reviews
• comparing local pizza parlors

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User-centered Design Example

• Your job figure out
• how people do their pizza ordering now
• how they would like to do it online
• what features would make sense when
• must also take into account the needs of the
  pizza parlor owners and workers.
• This is the needs assessment.
• Techniques
• Observation
• Interview
• Study existing successful designs

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User-Centered Design Example

• Observation
• Visit one or more pizza parlors. Observe how
  people achieve their pizza ordering goals.
• Observe what the counter people need to do.
  Optionally interview these people

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User-Centered Design Example

• Interview
• Prepare a list of questions about how people do
  their pizza ordering and what they would like in
  an automated ordering system.
• Interview at least three people about what they
  would like in an automated ordering system and
  how they would like it to work.
• Try to identify people with different needs and
  preferences, with respect to their attitudes
  about using online ordering systems.
• Ask them what, if anything, must be in the
  system in order for them to prefer it over a
  phone ordering system or an in-person ordering
  system.
• (E.g., no busy signals, cheaper prices,
  comparison shopping, faster service, or would
  they prefer anything over current methods.)
• Go look at at least one existing on-line
  food ordering web site and see how they handle
  these tasks.

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User-Centered Design Example

• Consider existing designs
• Look at least one existing on-line food ordering
  web site and see how they handle these tasks.

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User-Centered Design Example

• Procedure
• Answer the needs assessment questions
• Try to understand the basic tasks that are
  currently supported within pizza parlors and via
  phone orders
• Make a table showing
• user types
• tasks
• (guesses about) relative frequencies of tasks
• Decide which of the new tasks customers may
  perform using the new interface.
• Make note of which ideas you decided to drop
  based on your interviews.

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Needs Assessment Questions

• Who is going to use the system?
• What tasks do they now perform?
• What tasks are desired?
• How are the tasks learned?
• Where are the tasks performed?
• What is the relationship between the user and the
  data?

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Needs assessment Questions

• What other tools does the user have?
• How do users communicate with each other?
• How often are the tasks performed?
• What are the (time) constraints on the task?
• What happens when things go wrong?

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Task Analysis

• Characterize what happens when users perform
  typical tasks
• Tools
• table of user communities vs. tasks
• Who x What
• table of task sequences
• flowchart or transition diagram
• videotape depicting scenario

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How Often Do Users Perform the Tasks?

• Frequent users remember more details
• Infrequent users may need more prompting
• Which function is performed
• most frequently?
• by which users?
• optimize system for tasks that will improve
  perception of its performance

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Augment Table with Percentages(What percentage
of the is this task done by this person)(Numbers
are only suggestive, adapted from Shneiderman 98)
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User-Centered Design Example

• Scenarios
• Create three scenarios that will exercise these
  tasks in the proposed interface
• Create a description in which you outline
• A persons background
• Their goal(s)
• How they achieve these goals using the steps in
  the system
• Note this will change a bit when we use personas

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User-Centered Design Example

• Sketch an initial design
• Explain how the pizza ordering system will work.
• Either a textual description or a flow chart (or
  both) showing the sequences of steps that will be
  allowed in the system.
• Provide rough sketches showing at least three of
  the important screens.
• Walk through at least one of the scenarios you
  developed and show how it can be handled by the
  interface.