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					               Requirements
                Engineering


Southern Methodist University
         CSE 7316
User and Task Analysis
              Topics
Introduction to user and task
 analysis
Thinking about the users
Thinking about tasks
Thinking about the users
 environment
    What makes a product
          usable?
 They reflect the workflows that are familiar
  or comfortable
 They support the users learning styles
 They are compatible in the users working
  environments
 They encompass a design concept that is
  familiar to the users
 They have a consistency of presentation
Understanding how the user
    performs the task
 What the users goals are; what they are
  trying to achieve
 What users actually do to achieve those
  goals
 What personal, social, and cultural
  characteristics the users bring to the
  tasks
 How users are influenced by their physical
  environment
Understanding how the user
    performs the task
• How users previous knowledge and
  experience influence how they think
  about their work and the workflow
  they follow to perform their tasks
• What users value most that will make
  a new interface be a delight for them
  (speed? accuracy? help in
  recovering from errors? human
  contact? fun? challenge?)
Why isn’t this done already?
 Marketing knows the users
 The product is new - there aren’t any
  users to observe
 The users are all too different - we can’t
  possible visit all of them
 We don’t have enough time in the
  schedule
 We don’t have enough money in the
  budget
 Where does user and task
  analysis come from?
 Anthropology
   the study of people
 Ethnography
   practice of immersing oneself in a culture in
    order to describe that culture
 Cognitive psychology
   study of how people think and learn
 Rhetoric
   communicating with others through mediums
      Focusing on users
How do they think about their
 relationship to their work?
Is what you are developing related to
 their primary work or something they
 will use occasionally?
What and how much do they know
 about the subject matter you are
 designing for?
      Focusing on users
• What tools do they know how to
  use?
• What motivates them in doing their
  job?
• What motivates them in using their
  personal time at home?
• What technical skills do they bring to
  performing their work?
• What languages are they comfortable
  using?
 Users that must be studied
 Individuals who buy the software and use
  it without assistance or interaction from
  others
 Individuals who use the interface and
  information as part of their work, even
  though they did not buy the software
 Groups of people who use the software
  and information as part of a larger
  business process
 Those who administer the software
 Users that must be studied
 Individuals who repair products that are
  broken or who troubleshoot systems
 Those that install products for themselves
  and other and may also use the software
 Customers of the users and others who
  are affected by users working with the
  interface
   Starting a user and task
           analysis
Assemble a group of people in your
 organization who regularly interact
 with the users
  customer service
  training
  marketing
Brainstorm a preliminary list of users
 and potential users
   Starting a user and task
           analysis
• Create a user/task matrix or a
  user/characteristic matrix to serve as
  an initial model of your community of
  users
• Discuss the characteristics that you
  assume are typical of your user
  community
• Decide how to test your assumption
    Assemble a user profile
            team
 Salespeople who call or visit buyers and
  users
 Sales engineering people who install or
  customize products at user sites
 Marketing professionals will have
  conducted research studies
 Trainers who work with users in
  classroom settings
 Telephone support personnel
  Assemble a user profile
          team
Field support personnel
Consultants who study and advise
 on interactions with user
 communities
Former users who now work in your
 organization
   Brainstorm a list if users
 experience on the job
 education level
 background of training
 age, gender, physical differences
 geographic locations, wage differences
 language skills, terminology differences
 job level
   Create an initial user/task
            matrix
                               Tasks likely to be performed
Users        Getting         Basic        Advanced       Training   Customizing
             comfortable     user         software use   the        the software
             with software   difference                  patients
Patients           X             X
Patient            X             X              X
families
Novice                           X              X            X
clinicians
Expert                           X              X            X           X
clinicians
      Users and their jobs
 Do the users all have the same job title?
 Do the users have different job titles that
  reflect wide differences in skills and
  responsibilities?
 Are the users professionals who have
  learned aspects of their jobs in school?
 Do your users consider their jobs to
  define their modes of behavior?
Issues to consider about tasks
 How did your users learn to perform the
  tasks that they do?
 How long have they been doing these
  tasks?
 Have the tasks changed over time?
 Do the user perform many varied tasks in
  a typical day?
 Do the users teach others to perform the
  same tasks?
 Which people in the organization are
  considered the experts?
  Issues to consider about
            tools
 What tools are the users using today to
  perform their tasks?
 How did they learn to use these tools?
 How comfortable are they using the tools?
 Are the users familiar with technology that
  is similar to your intended design?
 To what extent do their tools define that
  they do?
      Mental models and
         vocabulary
Mental models are internal pictures
 of how things work
  a term from cognitive psychology
  vague, amorphous, individual, and
   changeable collection of associations in
   peoples minds
Users mental models will emerge
 through conversations with them
      Mental models and
         vocabulary
People use their mental models to
 make associations between
 information (words, pictures,
 sounds, smells) they are learning
 and information they already know
           Mental Models
 The picture of a trash can on a Mac is
  associated with a physical trash can used
  to throw something away (throwing away
  files)
 Designers also used trash can to eject a
  floppy disk from the drive - this confused
  users who thought that they would be
  “throwing away” the information on the
  floppy!!
    What is task analysis?
 Things related to goals and tasks
 “Things” are usually considered work
   admitting a patient to the hospital
   find a customers order in a database
   send a message to everybody on the project
    team
   put up a new web site
   change payroll codes
   set up a new computer at home
           Users goals
Users goals inside a company
  keeping my job
  getting done so I can go home on time
  Making the boss happy so I get a good
   review
Companies goals for users doing
 tasks
  increasing revenue
  increasing the number of applications
   that get processed
  decrease the cost of providing support
Norman’s seven stage cycle
Forming the goal
Forming the intention
Specifying the action
Executing the action
Perceiving the state of the world
Interpreting the state of the world
Evaluating the outcome
             Simple situation
 User forms goal                 Go outside to get some
 User forms intention             fresh air
  (decides task)                  Open the door
 User specifies action(s)        “It looks like I pull this
                                   handle here”
 User does the action(s)         Pulls on the handle
 User perceives the state of     The door didn’t open
  the world                       “Well that didn’t work. I
 User interprets the state of     guess I need to push it”
  the world                       Didn’t get outside yet. If
 User evaluates the               the user still wants to meet
  outcome                          the goal follow steps 3-7
                                   again this time pushing the
                                   door.
Different types and levels of
        task analysis
 How work gets done when several people
  are involved (workflow analysis)
 What a single individual does throughout
  the day or week or month (job analysis)
 How workflow analysis interacts with job
  analysis
 The order in which users do tasks
 How a large task is made up of subtasks
      Workflow analysis
Understanding how a particular
 process is accomplished if several
 people are involved in completing
 the work (business process analysis)
Many companies are trying to
 simplify business processes
Look for redundancies or
 unnecessary steps
      Filling a prescription
 At least two people involved
   patient
   pharmacist
 Others may be involved
   relative or friend
   caregiver
   clerk or assistant
   receptionist at doctors office
   doctor
      Filling a prescription
 Patient contacts the pharmacy
 Pharmacist or clerk takes the information
 Pharmacist looks up the patients
  prescription
 Pharmacist call the doctor for approval
 Receptionist send the call to the doctor
 Pharmacist waits for the call back
 After the call back the prescrition is filled
        Workflow analysis

 Workflow analysis is an important part of
  task analysis because the situation in
  which different types of people are
  involved in the process is much more
  common than processes individuals do
  alone
 If a task analysis is done by only looking
  at one part of the workflow the risk is that
  the product will not be used because it is
  in compatible with the rest of the workflow
             Job analysis
 Understanding all the work that a person
  does in a certain position during the day,
  week, or month
 Workflow analysis is a horizontal picture
  of how work moves across people
 Job analysis is a vertical picture of all the
  types of work that flow through a person
            Job analysis
Benefits
  find new marketing and development
   opportunities
  understand specific features to build into
   the product
  learn what pressures they are under and
   what they value
    Factors in job analysis
 Frequency (how often tasks are
  performed)
 Criticality (how important is each task)
 Time to complete (how time consuming)
 Difficulty (problems accomplishing tasks)
 Division of responsibility (do all the
  people in that job do this task?)
     Developing a task list
 A task is any observable, measurable
  action that has an observable beginning
  and an observable end.
 Task list for an e-mail program
   write a message
   send a message
   receive a message
   read a message that you received
   reply to a message
   save a message to look at it late
   forward a message
   send a formatted file with the message
    Process analysis, task
         sequences
 In an e-mail program these sets of tasks
  have a natural sequence
   write a message
     comes before
   send a message
   Receive a message from someone else

   reply to a message or
   forward a message to someone else
              Task Hierarchies
                        Job



  Task         Task           Task          Task




  Subtask     Subtask      Subtask


Task analysis is hierarchical. You can break up a job into
tasks and each task into subtasks
            Procedural analysis
                          Job

                           Start
You can carry a task
analysis down to the    Action (step)   Action (step)
individual steps and
decisions users make
                                           Other path
as they carry out the    Decision
task

                        Action (step)

                        Action (step)
                             End
                  Example task analysis
                                TV is off. VCR is off. TV and VCR
                                are set up and connected. No
User is using prior             cable box
experience; says other
machine worked from
buttons
                                User looks for buttons on front of
                                machine. Gets down on knees to do
                                this
                                                                     The light i this living
Are most VCRs kept                                                   room is too dim to see
this close to the floor?                                             the TV. Are most VCRs
                                Takes off bifocals to see better.
                                                                     used in dim lighting?
                                Complains that buttons are small
                                and black on black

Note that the user has tried
to solve the problem by trial
                                Opens front panel, reads labels,
and error, has not yet gone
                                says “Nothing here is relevant”
to the manuel.
   Ask about how he         Decides to use the manual. Says
   typically uses a         he can’t possibly read the whole
   manual                   thing


Inference: he jumped        Looks in table of contents. Finds
directly to a page part     section for setting the timer. Turns
way through the manual      to that page. Reads that he must get
because he just wants to    a menu up on the screen                It’s hard to hold a
get the task done, not                                             manual open and operate
learn anything more about                                          two remote controls at the
the VCR                                                            same time
                            Puts manual down. Picks up 2
                            remotes. Turns on TV with 1
                            remote. Turns on VCR with other.


                            Picks up manual again. Reads
                            “Press program button on remote
                            control. Does that
         Types of users
Any particular user at any particular
 moment in time with any particular
 product is at one of the four stages
 of use
  novice
  advanced beginner
  competent performer
  expert
  Characteristics of novice
           users
Fear of failure, fear of the unknown
Focus on accomplishing real work
Impatient with learning concepts
 rather than performing tasks
Theoretical understanding only - no
 practical experience
Characteristics of advanced
        beginners
Focus on accomplishing real work
Impatient with learning concepts
 rather than performing tasks
Randomly access tasks
By adding new and progressively
 more complicated tasks, begin to
 develop an empirically based mental
 model
      Characteristics of
    competent performers
 Focus on performing more complex tasks
  that require many coordinated actions
 Ability to plan how to perform a complex
  series of tasks to achieve a goal
 Willingness to learn how tasks fit into a
  consistent mental model of the interface
  as a whole
      Characteristics of
    competent performers
Interest in solving simple problems
 by applying a conceptual framework
 to diagnose and correct errors
   Characteristics of expert
         performers
 Focus on developing a comprehensive
  and consistent mental model of the
  product functionality and the interface
 Ability to understand complex problems
  and find solutions
 Interest in learning about concepts and
  theories behind a product’s design and
  use
 Interest in interacting with other expert
  users
Thinking about the users’
      environment
      Why is environment
         important?
People do not perform their work in
 isolation
Influenced by the activity around
 them
  physical characteristics of the
   workplace
  type of equipment being used
  work relationships with other people
Product must fit into environment or
 it will be frustrating to use or be
 rejected
        What aspects are
          important?
 Physical environment
   light levels
   placement of controls
   amount of space to work in
   noisy or quiet
   dirt, dust, pollution
   temperature, humidity
   power availability
   dangers in the environment
        Working at home?
 Users in an office
   will probably have a T1 line
 Users at home may
   have a slower modem
   may require different strategies for getting the
    information they need
   may need a longer power cord
   automatic save feature (disruptions from kids)
         Adequate space?
 “Standard” may not be so standard
 Is there room for a mouse or detached
  keyboard?
 Is there room for paper manuals or should
  on-line help be used?
 Adequate space for optimal viewing
  angle?
 Bookcases in Japan are narrower then in
  US
   cubicle walls are rare
     A noisy environment?
 Noisy environments make learning more
  difficult
 Sound cues (bells, beeps, etc) may
  distract co-workers
 Will they be able to hear the audio tones
   people with hearing aids have a hard time
    hearing in the presence of background noise
     Dirt, dust, and wind
Will touch screen be usable if the
 screen smears from oil?
Working in a cleanroom may require
 no paper (manuals) at all
Dust can make computers unusable
Wind can make the use of manuals
 and paper almost unusable
  maintenance technicians
        Adequate lighting
 Can the user see the screen? The
  manuals? The controls?
 Can they see the images in dim light?
 Will colors for warnings or cautions be
  adequately visible on the screen?
 VCR black on black buttons hard to see
   probably designed in a bright lab
           Temperature
Extremes of temperature and
 elevation
  disk drives have a hard time working at
   high elevations because there is not
   enough air to float the disk above the
   read mechanism
Cold temperatures make it difficult to
 use controls
  will users be wearing gloves?
High temperature and humidity may
 fog screens or make hands slip
   How quickly must they
          react?
Users may be measured by how
 quickly type can react (customers
 standing in line)
Are they in any danger?
  what happens when the users make
   mistakes?
  ATM machines are a focal point of
   robberies
       What aspects are
         important?
• Social environment
  – are tasks performed quickly and/or
    accurately
  – resources available to answer
    questions
  – do people who share info work in same
    location
  – social hierarchy in the organization
  – how do physical and social
    environments interact
  – relationship between users and
        What aspects are
          important?
• Cultural environment
  – national cultural influences
  – work in different cities, states, regions,
    etc
  – professional culture with particular
    values
Making the business case
     for site visits
 Verifying your assumption
Primary reason for traveling to user
 sites is to challenge or verify your
 assumptions
May meet with resistance to
 watching users and listening to them
The users doing the new process will
 be the same users that did the old
 process!
Very rare that a new product is so
 new that there is nothing in existence
 to study
     Preparing a business
          proposal
Analyze the return on investment
  changes later are more expensive
Meeting or exceeding the
 competition
  are they doing usability studies
Calculating the time required to
 conduct an analysis
     Preparing a business
          proposal
            Task              Hours per task   Labor cost per task
Brainstorming and initial          80                $5600
user/task matrix and
outlining the proposed site
Planning the site visit             34               2380
Recruiting participants             42               2940
Conducting six days of site        120               8400
visits/two observers
Analysis and report                 80               5600
Total hours and labor costs        356              $24,920
     Selecting Techniques
Contextual inquiries; a philosophy
 as much as a technique
  Plan (understand the issues for the
   visit)
  Select the users to represent the right
   diversity
  Treat the users as a partner
  Watch, listen and talk with users about
   their work
  Make the conversation concrete
  Take your cues from the user (make
   sure you are interpreting things
   correctly)
            Techniques
Get the user to talk aloud while doing
 the task
  determine the users mental models
Talk right after the task (if you can’t
 do it during the task)
  sometimes it is best to be a “fly on the
   wall”
            Techniques
When to be unobtrusive;
  the task involves helping another
   person (call on the phone, etc)
  the task involves safety (air traffic
   controller)
  the task requires a high degree of
   concentration (solving complex
   mathematical problems)
  you are timing the task
  the user is on a deadline (working under
   pressure)
  Role playing and staged
         scenarios
Not as credible as data collected
 under actual circumstances (this was
 done for the AA SABRE travel info
 Network)
Must have relevant scenarios
Advantage is that you can use the
 same scenario at several sites and
 observe different users handle the
 same scenario
 Cue recall with videotapes
Sometime, users do not want or do
 not have the time to interview and
 talk but are willing to be videotaped
Questions can be answered later
 about tasks that need more
 explanation or interpretation
  Doing a process analysis
 Interview and ask questions
   when does the first task in the process happen
   what triggers it
   who does it
   what information is required to do the task
   what are the major steps in the task
   who is the next person in the chain of the
    process
   when does the next task happen
   Ethnographic interviews
 “Top down” approach
 Start by getting a general framework from
  the users
 Use that knowledge to structure and
  understand future observation
 Contextual inquiry, on the other hand, is
  bottom up (observing and gathering large
  samples of work and then develop
        Collecting artifacts
 Artifacts can be paper or screen shots
 “cheat sheets”
 forms that trigger data entry or the start of
  a process
 forms and reports that get printed at
  various times during a process
 examples of output from tasks
 hand-written notes or logs as reminders
       Collecting stories
Gather stories of real situations
“critical-incident technique” - a way
 to gather stories in a short period of
 time
  ask each interviewee to recall a specific
   critical incident
  then probe for more information about it
  questions are planned in advance
  iterate
  can be used as a base for scenario-
   based design
  Working with users away
    from the work site
 Sometimes it is hard to go to the users
  site
   security reasons
   equipment that is not portable to the users site
 Usability lab
 Conference room
 Ask the users to bring example of real
  work
Market research techniques
 Meet with users in focus groups
   facilitator skilled in asking questions, getting
    opinions, etc
   focus groups don’t show behavior
 User surveys
   designed to gather information from a large
    group of people (direct-mail questionnaires,
    telephone survey, fax, web)
 Meeting users at trade shows
                    Other
 Bringing users to requirements-gathering
  sessions
   focus on functionality rather than usability
   what users say may not be what they do
   users talk about the typical case
   what they need may not be the best way to
    solve the problem
   group dynamics problems
 Including a user on the design team
             Conclusion
 Requirements elicitation is a collaborative
  decision-making activity involving users,
  developers and customers
 Dependent on the diversity and
  experience of the problem being
  formulated
 Techniques should be tailored to the
  project

				
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