Task Hierarchy by HC120912214420

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									Workflow Analysis

  Describes how work is done when
 several people are involved
  Coarsest level of granularity
  Provides an overview
Workflow Analysis
   Professor records grades, gives to secretary.
   Secretary collates all grades from professors, sends to registrars office.
   Registers office records receipt of grads, sends them to Information services.
   Clerk transfers grades into database.
   Operator prints grades for each student.
   Postal machine operator stuffs envelops and stamps them.
   Transportation person takes all letters to Post Office.
Job Analysis

Focuses on a what a single person does in
 the course of a day, week, or month
Looks at all tasks a single person does
Job Analysis

Example, Receptionist:

   Call Security to get parking permit for visitor.
   Schedule a meeting with prospective client.
   Refer incoming calls to customer service.
   Call for copier service.
   Check inventory of office supplies.
Task List

More detailed look at Job Analysis
Focuses on one component of job
One task and how it is broken down
important to be consistent of level of
 detail
Reasonable number of tasks
Task Sequences

Establish order in which tasks are
  performed
Example:
     Write letter
     Address the envelope
     Put letter in envelope
     Place stamp on envelope
Task Sequences

Order can be different
Example:
     Address the envelope
     Write letter
     Place stamp on envelope
     Put letter in envelope
Task Sequences

Sequences can be constrained because:
  Physical Realities
  Tradition
Task Hierarchies

Document the components of a task, called
 sub-tasks
Can show how sub-tasks are compriased of
 actions
Level of detail is dependent on type of site
Task Hierarchy
Procedural Analysis

Contains the most detail
Depicts individual steps of tasks
Shows flow of control
Considers constraint of user interface
Shows how users carry out tasks
Procedural Analysis
Environmental Analysis

Considers local of usr with using site
Typically home or office
Could be:
  outdoors (information kiosk)
  factory floor
  Extreme weather
  handheld device
Observing and listening to
users

Discussed what you need to consider
How did you gather required information?
Observing and listening to
users

Thinking aloud
Talk Right After
Role Playing
Cueing Recall
Other Techniques
Thinking aloud

Running commentary on users work as
 they perform it
Encourage users to explain what they are
 doing and why
Keep the user talking
Talk Right After

If user cannot talk talk while performing
 job: customer service
Ask user about job once they have time to
 talk
Perform remotely
Role Playing

Find out about infrequent tasks
Scenario-base approach
Pretend to be a user
Not as credible
Not as useful
Cueing Recall with videotape

Useful when do not want to interfere with
 user
Record user’s activities with camera
Review tape with user, ask about tasks
Other techniques

Focus groups
Mailed surveys
Recruiting Users

Where to find users?
Primary access from site’s customers,
 users, clients
Other sources….
Employment Agencies

Good source of end users
Can request certain types of users
Expect to pay
Might get biased users
Market Research Firms

Finds specific type of users
No expectation of job
Can be expensive
Less concern about biasing users
Other Possibilities

College campuses
Newspaper advertisement
Customer lists
User Groups
How Many Users?

Depends on what you need to learn
Size of site
Number of unique user types
Enough for breath of representation
Might be a moving target
Usability Specifications

Answers: How good is a web site?
Defines the means to measure the
 success of a site
Used during evaluation phase of
 development lift cycle
Helps define what to look for
Usability Specifications

Two categories of specifications:


Qualitative
Quantitative
Quantitative Specifications

Performance measure
Quantifiable measure: expressed as numbers
Directly observable
Directly measurable
Example:
   Time to complete a task
   Number of tasks completed
   Number of errors committed
Qualitative Specifications

Preference measure
User’s opinion
Not directly observable
Examples:
  First Impression
  Ease of use
  long-term satisfaction
Qualitative Specifications

How to measure?
Likert scale: means to quantify preference
Example:
                         Strongly   Disagree   Neutral   Agree   Strongly
                         Disagree                                 Agree
   Overall the site is      1          2          3        4        5
   easy to use
   When I searched          1          2          3        4        5
   for an item, the
   result were useful
   I could find             1          2          3        4        5
   everything I was
   looking for
   I could pay for          1          2          3        4        5
   my purchases
   easily
Usability Specifications

More usability specification examples:

Usability Software
Bohmann Usability Specifications
Usability Specifications
Software for Usability
Memory

Role of memory in usability
Based on model of human memory:
Memory

Short-Term memory is small
Long-Term memory stores large amount
 but fallible
Memory

Chunking
Break large data into smaller more
 recallable chunks
SSN vs Drivers license number
URL Design

								
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