Imran Hussain

1
Virtual University Human-Computer Interaction
Lecture 41Asking Users and Experts

• Imran Hussain
• University of Management and Technology (UMT)

2
In Last Lecture

• How to observe users
• Field studies
• Usability testing
• How to collect data while observing user

3
In Todays Lecture

• Users
• Interviews
• Questionnaires
• Experts
• Inspections
• Walkthroughs

4
Types of Interviews

• Unstructured interviews
• Structured interviews
• Semi-structured interviews

5
Types of Interviews

• Interviews may be conducted to ask user about
  certain aspects of an application
• Unstructured - are not directed by a script. Rich
  but not replicable.
• Structured - are tightly scripted, often like a
  questionnaire. Replicable but may lack richness.
• Semi-structured - guided by a script but
  interesting issues can be explored in more depth.
  Can provide a good balance between richness and
  replicability.

6
Things to avoid when preparing interview questions

• Long questions
• Avoid compound sentences by splitting them in two
• Jargon language that the interviewee may not
  understand
• Leading questions that make assumptions e.g., why
  do you like ?
• Unconscious biases e.g., gender stereotypes

7
The interview process

• Dress in a similar way to interviewees if
  possible, if in doubt dress neatly and avoid
  standing out.
• Prepare a consent form and ask the interview to
  sign it
• If you are recording the interview which is
  advisable make sure equipment works in advance
  and you know how to use it.
• Record answers exactly and do not made any
  cosmetic adjustment , correct or change answers
  any way

8
Preparing for unstructured interview

• You have an interview agenda that supports the
  study goals and questions
• Be prepared to follow new lines of inquiry that
  contribute to your agenda
• Pay attention to ethical issues
• Work on gaining acceptance and putting the
  interviewees at ease
• Respond with sympathy if appropriate but be
  careful not to put ideas into the head of
  respondents
• Always indicate to interviewee the beginning and
  the ending of the interview session.
• Start to order and analyze your data as soon as
  possible after the interview.

9
Probing

• Start with some preplanned question and then
  probes the interviewee to say more
• Example
• Which web sites did you visit more frequently?
• Why do you like this web site?
• Tell me more about web site x?
• Any thing else?

10
You can also make use of Probes and prompts
11
Group interviews

• Also known as focus groups

12
Questionnaires

• Make the questions clear and specific
• When possible ask closed questions and offer a
  range of answers.
• Consider including no opinion option for the
  questions that seek opinion.
• Think about the ordering of questions
• Avoid complex multiple questions
• When scales are used make sure that range is
  appropriate.
• Make sure that the ordering of scale is intuitive
  and consistent.
• Avoid jargon and consider when you need different
  versions of questionnaires for different
  population.
• Provide clear instructions on how to complete the
  questionnaires.

13
Questionnaire style

• Questionnaires can have various styles and can
  have various formats
• Questionnaire format can include- checkboxes-
  ranges- Likert rating scales

14
Encouraging a good response

• Ensure questionnaire is well designed
• Provide short overview section
• Include a stamped self-addressed envelop for its
  return
• Explain why you need the questionnaire to be
  completed
• assure anonymity
• Contact respondent through a follow-up letters
  ,phone calls, or emails
• Offer incentive such as payments

15
Advantages of online questionnaires

• Responses are usually received quickly
• copying and postage costs are lower than paper
  surveys
• Data can be collected in database for analysis
• Time required for data analysis is reduced
• Errors in questionnaire design can be corrected
  easily

16
Nielsens heuristics

• Visibility of system status
• Match between system and real world
• User control and freedom
• Consistency and standards
• Help users recognize, diagnose, recover from
  errors
• Error prevention
• Recognition rather than recall
• Flexibility and efficiency of use
• Aesthetic and minimalist design
• Help and documentation

17
Web heuristics

• Following heuristics are more useful for
  evaluating commercial websites
• Does the web site have high quality content
• Is the web site often updated
• Does the website offer minimal download time
• Does the web site ensure ease of use
• Is the web site relevant to the user need

18
Discount evaluation

• Heuristic evaluation is referred to as discount
  evaluation when 5 evaluators are used.
• Empirical evidence suggests that on average 5
  evaluators identify 75-80 of usability problems.

19
Cognitive walkthroughs

• Involve simulating a users problem solving
  process and each step in the human computer
  dialog checking to see if the users goals and
  memory for action can be assumed to the next
  correct action

20
Steps of Cognitive walkthroughs

• Characteristics of typical user are identified
  and documented and sample tasks are developed
  that focus on the aspects of the design to be
  evaluated
• Designer and one or more expert evaluators than
  come together to do analysis
• Evaluators walk through the action sequences for
  each task placing it within the context of
  typical scenario
• As the walkthrough is being done, record of
  critical information is compiled
• Assumption about what would cause problems? Why
  are they recorded?
• Notes about site issues and design changes are
  made
• Summary of the result is compiled
• Design is revised to fix the problems presented

21
Why they do this?
22
The 3 questions

• Will the correct action be sufficiently evident
  to the user?
• Will the user notice that the correct action is
  available?
• Will the user associate and interpret the
  response from the action correctly?

23
Pluralistic walkthrough

• Can be conducted by following sequence of steps
• Scenarios are developed in the form of series
  part of the screen representing a single path to
  the interface
• Scenarios are presented to the panel of
  evaluators and panel is asked to write down
  sequence of actions they would take to move from
  one screen to another
• When evaluator has written down their actions the
  panelist discuss the actions they have suggested
  for that ground of the review
• Usually the representative user go first so that
  they are not influenced by other panel members
  and are not uttered from speaking
• Usability experts present their findings and
  finally designers offer their comments
• Panel moves on the next ground of the screen.
  This process continues until all the scenarios
  have been evaluated