Review For Final Exam

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• Review For Final Exam

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Question 1

• Explain the following terms
• Affordance
• Visibility
• Feedback
• b. Give an example of good affordance from a
  mobile telephone.
• c. Give an example of good visibility from a
  mobile telephone.
• d. What is the relationship between feedback and
  affordance?

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Solution 1

• a.
• Affordance An aspect of an object that makes it
  obvious how the object is to be used.
• Visibility the properties of an object that make
  it obvious what is used for.
• Feedback Information sent back to the user to
  confirm what action has been done and/ or what
  result has been accomplished.
• b. Example of good affordance The send button is
  raised and button shaped suggesting that it
  should be pressed. It is also a different color,
  making it stand still.

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Solution 1 (cont..)

• c. Example of good visibility the number is
  printed on each button, suggesting that when the
  button is pressed, that number will be displayed
  on the screen and will be dialled (immediately or
  after the whole number has been entered,
  depending upon the phone).
• d. The relationship between feedback and
  affordance affordance is similar to feedback as
  it tells the user how a control is operated.

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Question 2

• (a) What is a mental model?
• Describe 2 characteristics of mental models that
  might influence interaction, giving examples of
  how these might influence a user interacting with
  a word processor.
• (b) Define in detail what is meant by an
  interface metaphor, giving an example.
• (i) How can an interface metaphor influence
  the learning of a new computer system?

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Solution 2

• (a) "A mental model is a mental representation
  that people use to organize their experience
  about themselves, others, the environment and the
  things with which they interact.
• Characteristics
• They are usually incomplete e.g. the user may
  not know how to use style sheets in this WP.
• They contain errors e.g. The user may belive the
  save icon allows you to specify the file name
  (this is not true in MS Word).
• Can be run e.g. the user may anticipate how he
  would alter the margins stepping through this
  action in his mind before actually doing it etc.

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Solution 2 (cont..)

• (b) An interface metaphor is the metaphorical use
  of words on the screen, static images and icons,
  and interactive graphics. These elements are used
  metaphorically when the designer deliberately
  draws upon the users existing knowledge.
  
• An example may be the calculator that comes
  with Windows.
• (i) It draws in the users knowledge of a
  familiar domain and allows him or her to form an
  accurate mental model more quickly.

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Question 3

• (a) Define the term interaction style.
• (b) Choose two distinct types of interaction
  style. For each
• (i) Describe the interaction style
• (ii) Explain how it supports (or does not
  support) the Planning an action sequence stage in
  the human-action cycle
• (iii) Explain how it supports (or does not
  support) the Perceiving what happened stage in
  the human-action cycle
• (iv) Give a brief example illustrating when the
  interaction style would be used and why its use
  would be appropriate.

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Solution 3

• An interaction style is a collection of user
  interface controls and their associated behavior
  from which a designer can choose. The interaction
  style provides both the look (appearance) and
  feel (behavior) of the user interfaces,
  indicating the way a user will communicate with
  the system.
• Two distinct types of interaction style
• Command line
• Direct manipulation

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In terms of Command Line

• (i) User enters a command from a formal command
  language this tells the computer what to do.
• (ii) Planning an action sequence doesnt help
  much because the user is required to recall the
  different (often esoteric) commands.
• (iii) Perceiving what happened again it doesnt
  help much because often very limited feedback is
  provided.
• (iv) Use some operating systems. This is
  appropriate because most operating systems are
  used by experts who already know the commands and
  who have a good mental model of what is going on
  inside the machine.

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In terms of direct manipulation

• (i) User manipulates screen objects to control
  the computer (operates in a manner analogous to
  the real world).
• (ii) Planning an action sequence helpful
  because the possible actions are visible
• (iii) Perceiving what happened again helpful
  because the effect of the action is immediately
  visible
• (iv) Used in GUI interfaces. This is appropriate
  because many GUIs are used by novices who need
  support through the interaction process the
  emphasis on recognition rather than recall really
  helps.
• (Similarly for menus, form-fill or
  anthropomorphic interaction styles)

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Question 4

• (a) What is the primary purpose of evaluation in
  user interface development?
• (b) Describe what is meant by heuristic
  evaluation and highlight four ways in which it
  differs from user observation.
• (c) Identify two benefits and two limitations of
  heuristic evaluation.
• (d) Would you use heuristic evaluation if you
  were developing an interface for the control
  panel of a new space craft? If so, explain how it
  would fit within your evaluation plans. If not,
  justify your decision.

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Solution 4

• (a) To assess the UI against its usability
  requirements.
• Give one half mark for assessing and one half
  mark for usability requirements.
• Total 1 mark
• (b) Heuristic evaluation is a form of inspection
  where an inspector evaluates the UI against a set
  of guidelines or standards. It differs from user
  observation because
• 1. inspectors are used instead of users,
• 2. the session does not need to be carried out in
  the realistic setting,
• 3. recording of the session is not necessary
  because the inspectors write defect reports,
• 4. heuristic evaluation can be quicker and
  cheaper than running user observations. 3

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Solution 4 (Cont..)

• 4. heuristic evaluation can be quicker and
  cheaper than running user observations.
• See Chapter 26 for a description of heuristic
  evaluation. Give 1 mark for description of
  heuristic evaluation and one half mark for each
  of the four differences.
• (c) Chapter 26 lists 3 benefits and 4
  limitations.
• Benefits
• Inspections can be less expensive than
  user-observation
• During an inspection, inspectors more often than
  not suggest solutions to the usability defects
  that they identify

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Solution 4 (Cont..)

• It can be annoying to discover a large number of
  obvious errors during a user-observation session.
  Inspecting the UI first can help reveal these
  defects.
• Limitations
• As usability inspectors often do not involve real
  or representative users, it is easy to make
  mistakes in the prediction of what actual users
  will do with the UI
• Inspectors often differ from real users in the
  importance they attach to a defect
• Inspectors may have their own preferences, biases
  and views towards the design of user interfaces
  or interaction design, which in turn may bias the
  evaluation data
• The evaluation data from inspection is highly
  dependent on the skills and experience of the
  inspectors.

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Solution 4 (Cont..)

• (d) Using heuristic evaluation would be useful to
  detect any obvious errors in the interface, and
  would avoid wasting the time of real users.
  However, operating this kind of interface is
  highly skilled and finding a suitable inspector
  would be difficult because of the specialist
  knowledge required. In general, real users find
  it difficult to understand heuristics and so it
  would not be appropriate to involve a real user.
  It would be essential to back up heuristic
  evaluation with user observations.
• Alternatively, heuristic evaluation may be
  considered as inappropriate because of the
  difficulty of finding a suitable inspector.

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Question 5

• Listed below are three main preparation tasks to
  be carried
• out before running an evaluation session. For
  each of them, describe what is involved and give
  one advantage of performing the task
• (i) Producing an evaluation plan
• (ii) Writing an evaluation script
• (iii) Running a pilot test

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Solution 5

• (i) Producing an evaluation plan involves making
  choices regarding the evaluation technique, the
  participants, the evaluators, task description,
  and location. The evaluation plan outlines how
  the evaluation sessions will be conducted.
  Advantages of producing such a plan include being
  well-prepared for the sessions, and knowing that
  all the important decisions have been made.
• Describing what is involved in producing an
  evaluation plan should include each of the five
  aspects. Give 1 mark for describing each aspect
  of the evaluation plan, and 1 mark for a suitable
  advantage.

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Solution 5 (Cont..)

• (ii) Writing an evaluation script involves
  writing down the words that will be spoken to
  each participant, together with instructions,
  e.g. when to give the consent form etc. An
  advantage of having a script is that it is easier
  to remember all the steps in the procedure, and
  to be consistent with all participants.
• (iii) Running a pilot test involves performing an
  evaluation session to check that your plan will
  work. The pilot session is run with participants
  who are representative of your end users. The
  advantage of running a pilot session is that you
  can practice your evaluation materials before the
  real evaluation sessions are run. No matter how
  much you plan the evaluation session, unexpected
  events occur, and people will do things you dont
  expect.

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Question 6

• In the context of Travel Organiser, identify six
  specific considerations that should be taken into
  account when designing the user interface. Your
  answers must be drawn from any or all of the
  following areas.
• users
• tasks
• the environment
• Justify why each consideration is important, and
  briefly outline how it could be addressed by the
  user interface design.

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Solution 6

• Users computer experience. There will be a wide
  variety of computer experience in the user group,
  so the system needs to be designed with novices
  and experts in mind.
• Users physical abilities. Users may be of any
  age, and of any abilities. The system should be
  designed with accessibility issues in mind with
  such a wide variety of potential users.
• Users motivation. Users may be highly motivated
  to sort out their holiday, but they are unlikely
  to be very patient with a system that takes a
  long time.

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Solution 6 (Cont..)

• Task regularity. Users are likely to use the
  system infrequently, possibly only once ever.
  They will not need to access their data once the
  session has been completed. Travel Organiser will
  need to be easy to use on the first attempt.
• Task. Use of the system is likely to be
  interrupted, but the data would not be kept if
  the client does not complete the session.
• Task. The nature of the task involves a set of
  simple questions. This would be addressed using
  menus in a question and answer format.

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Solution 6 (Cont..)

• Environment. The system is to be designed for use
  in the travel agents, so the environment is
  likely to be noisy, and possibly dusty. The
  machine can be placed somewhere to maximise light
  effectiveness.
• Two marks each one for why each consideration is
  important in the context of this scenario, and
  one for how the UI might address it. Chapter 4
  offers the following
• User characteristics age, sex, culture, physical
  abilities, educational background, computer/IT
  experience, motivation, attitude.
• Task characteristics variability of task,
  regularity of tasks, knowledge and skills
  required, time criticality, safety hazards, alone
  or with others, task switching.
• Environment characteristics social, physical and
  organisational.

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Question 7

• (a) Write two brief distinct use scenarios for
  Travel Organiser. These should demonstrate how
  users would interact with the system. For each,
  explain the benefits such a system would provide
  to the user carrying out his task in the
  particular environment.
• (b) Suggest two distinct possible input devices,
  other than the standard QWERTY keyboard and
  mouse, and two distinct possible output devices
  that would be appropriate for Travel Organiser.
  For each device, describe its operation and the
  advantages and disadvantages of its use in this
  context.
• (c) Suggest an appropriate interaction style for
  this system, again considering the advantages and
  disadvantages of the suggested interaction style
  in this context.

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Solution 7

• (a) Johnny Williams is a young bachelor looking
  for an adventure holiday. He is keen on most
  sports and has tried skiing and body-boarding
  before, but this time is looking for something
  different. He's not too bothered about where he
  travels, provided it is somewhere with a lot of
  people. He has seen WalHal Travel advertised and
  wants to explore the possibility of having a
  tailor-made holiday. He walks up to the
  TravelOrganiser and chooses the option to see
  some example holidays. These look interesting,
  but there is nothing particularly exciting for
  him. He then looks at the options for different
  activity holidays. Here there is a long list
  including pot-holing, skiing, surfing,

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Solution 7 (cont..)

• scuba-diving, and many others that Johnny has
  considered before. Then he spots kite surfing. He
  has not heard of this before, and so he looks at
  the description. This appeals to him, and so he
  then wants to find out where he can go on holiday
  to do this. Having got the list of places, he
  prints off his findings and takes them away to
  find out more about the sport and its locations.
• The benefit to Johnny is that he is able to find
  out the kinds of activities on offer, without
  having to wait in a long queue to meet with the
  travel agent.
• Harriet Smith is retired and is looking to
  have a holiday of a life time. She hasnt done
  much traveling in her life, is frightened of
  flying, and cant drive.

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Solution 7 (cont..)

• She is also rather shy of talking to travel
  agents but would prefer to look through printed
  brochures. Unfortunately most of the holidays she
  has found in brochures involve flying or driving.
  She approaches the Travel Organiser and although
  she is not very good with computers, she finds
  the interface appealing and easy to follow. She
  begins by looking at some example holidays. One
  of these is a cruise on the Danube. She had
  considered a cruise before, but had only found
  holidays involving sea crossings, but she didnt
  like this idea. A river cruise sounds much more
  interesting. In this example holiday, though, the
  client traveled by air. Harriet doesnt want to
  fly, and

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Solution 7 (cont..)

• so she goes to the travel options and finds
  that she might be able to travel there by train
  and hydrofoil. She prints off the example holiday
  and takes it across to the travel representative
  to discuss her specific options.
• The benefit to Harriet is that she can take
  her time to explore the options and then be more
  confident in talking with the representative.

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Solution 7 (cont..)

• (b) Input device.
• Tablet could be used to input choices.
• Advantage easy to use by all levels of
  expertise.
• Disadvantage users with limited dexterity may
  have difficulty.
• Touch Screen to choose the options available
  on the screen.
• Advantage easy to use, no peripherals to get
  lost or broken.
• Disadvantage limit to the number of options
  that can feasibly be displayed on the screen.
• Output device. (only two required)

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Solution 7 (cont..)

• Screen a good quality screen is required to
  give good color rendition.
• Advantage Good for displaying images of hotels
  and resorts.
• Disadvantage Could be expensive if WalHal is a
  nationwide chain.
• Printing device to output a list of choices to
  take to the agent.
• Advantage allows a hard copy to be carried
  about.
• Disadvantage need to keep paper and ink full,
  and possibility of litter as unwanted printouts
  are left lying around.

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Solution 7 (cont..)

• Wall-mounted display a large screen.
• Advantage groups of users can comfortably view
  the information together.
• Disadvantage others in the shop can also see
  the display and this lack of privacy may inhibit
  the systems use.
• 1½ marks each ½ mark each for naming and brief
  description advantage disadvantage. Note the
  use of distinct in the question. If answer only
  names the device without any description, this
  does not get the half mark.

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Solution 7 (cont..)

• (c) Interaction style
• Menu-based system is likely to be most
  appropriate. Advantage easy to guide users
  through the material. Disadvantage unlikely to
  be able to include all the possible options and
  users may get a wrong impression of how many
  options are possible.
• Only one interaction style is required. Just
  naming the interaction style gets nothing.
• Give 1 mark for advantage and 1 mark for
  disadvantage. The answer must be linked to
  context, but if the context is implicit in this
  answer, and it has clear links to thinking from
  earlier parts of the question, then this is
  acceptable. The advantages and disadvantages must
  refer to the interaction style and not the
  hardware.