1. Task Analysis
IST 331 – Organization and Design of Information Systems: User and System Principles
Instructor: Mithu Bhattacharya
Spring 2011

2. Class Objectives Midterm Teaching Evaluation Discuss Midterm 1
Introduction to Task Analysis
Perceptual Interaction Lab
March 14th, 2011

3. IST 331 Midterm 1
Mean: 85.76
Median: 88.25
Minimum: 57
Maximum: 100

4. Task Analysis Find out Observe existing work practices
Who the intended customers / users are
What tasks they need to perform
Observe existing work practices
Create scenarios of actual use
Try-out new ideas before building software
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5. Why Task Analysis? System will fail if it
Does not do what the customer needs
Is inappropriate to the customer
“The system must match the customers’ tasks”
Why not define “good” interfaces?
Infinite variety of tasks & customers
Guidelines are usually too vague
e.g.,“give adequate feedback”
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6. Uses of Task Analysis
To enable us to understand how well a new system ‘fits’ old system
To compare designs
To perform a system check to see if system will support all of user’s tasks
To create manuals for users
To suggest where users will make mistakes
To teach users how to perform tasks
To allocate tasks to users in teams
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7. Hierarchical Task Analysis
Involves decomposing goals into sub-goals
Easiest to use task analysis approach
Uses both graphical and textual versions
Time consuming but simple process
Does not tell when to stop
Provides useful information to inform design early in the design process
Does not make detailed suggestions
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8. Hierarchical Task Analysis Example
Login
Select login screen
Enter ID
Enter password
Choose objects
Browse listing
Select item
Pay
Choose pay screen
Select payment method
Enter payment method details
Plan: Task 1, then Task 2 as many times as needed, then Task 3.
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9. Cognitive Task Analysis
Focuses on what users already know
Concerned with accurate mapping between representation of user’s knowledge and that required by system
CTA used where operators are well trained
Pays attention to how tasks are performed along with noting the tasks
e.g. “how long users will take to perform the tasks”
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10. Task Analysis Questions
Who is going to use system?
What tasks do they now perform?
What tasks are desired?
How are the tasks learned?
Where are the tasks performed?
What’s the relationship between user & data?
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11. Task Analysis Questions (contd.)
What other tools does the customer have?
How do customers communicate with each other?
How often are the tasks performed?
What are the time constraints on the tasks?
What happens when things go wrong?
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12. Who? Identity? Background Skills Work habits and preferences
In-house or specific customer is easy
Need several typical customers for broad product
Background
Skills
Work habits and preferences
Physical characteristics
Height?
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13. Talk to Them Find some real customers Talk to them Are they too busy?
Find out what they do
How would your system fit in
Are they too busy?
Buy their time
T-shirts, coffee mugs, etc.
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14. What Tasks? Important for both automation & new functionality
Relative importance of tasks
Observe customers
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15. How are Tasks Learned? What does the customer need to know?
Do they need training?
Academic
General knowledge / skills
Special instruction / training
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16. Where is the Task Performed?
Office, laboratory, point of sale?
Effects of environment on customers?
Customers under stress?
Confidentiality required?
Do they have wet, dirty, or slippery hands?
Soft drinks?
Lighting?
Noise?
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17. What is the Relationship Between Customers & Data?
Personal data
Always accessed at same machine?
Do customers move between machines?
Common data
Used concurrently?
Passed sequentially between customers?
Remote access required?
Access to data restricted?
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18. What Other Tools Does the Customer Have?
More than just compatibility
How customer works with collection of tools
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19. How do Customers Communicate With Each Other?
Who communicates with whom?
About what?
Follow lines of the organization? Against it?
Example: Assistant to manager
Installation of computers changes communication between them
People would rather change their computer usage than their relationship
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20. Task Analysis Methods Lots of task analysis methods
None completely satisfactory
Best solution is to employ a variety of methods
Questionnaires and Interviews
Observational studies
Examination of competing or similar products
Use unsolicited comments
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21. Questionnaires & Interviews (1)
Talk to a number of representative users
Talk to key users
Plan questionnaire / interview
Preset questions to address issues identified in advance
Always provide flexibility for users to add to your plan
Provide mechanism for recording data easily
Present quantitative results
Keep the number of questions low
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22. Questionnaires & Interviews (2)
When deciding to ask a question, always ask
Why is this question included?
How will I analyze results of this question?
Do I lose anything if I leave it out?
Do I have a better source for this information, e.g., can I find it by looking at logs?
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23. Questionnaires & Interviews (3)
Ask clear questions
Can the user understand your question?
Ask questions that users can answer validly and reliably
Does the user store information in this way?
Does the user remember such information?
Will the user be inclined to answer your question truthfully?
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24. Questionnaires & Interviews (4)
If you need the answer, but users can’t give it to you, use another technique
If a question won’t give the answer, look for the user leaving traces in the environment
Respect users time and intelligence
Always thank the user for your information
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25. Observational Studies (1)
Describe and analyze current practice
Note organization of functionality
Note expectations and concerns of current users
Solicit suggestions from users
Collect quantitative data
How many?
How often?
How long?
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26. Typical Observation Techniques (2)
Task process study
Detailed steps in tasks performed by users recorded
Tools study
Types of tools used by users recorded
Time and duration of tool usage also recorded
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27. Typical Observation Techniques (3)
Time diary
Users log their use of time throughout day
Random recordings of time usage set off by beeper on watch
Communication diary
Users log each communication and purpose of communication
Context inquiry
Observer in context
March 14th, 2011

28. Principles: Interpretation (4)
Good facts are only the starting point
Designs based on interpretations
Validate & rephrase
Run interpretations by user to see if you are right
Share ideas to check your reasoning (Member checking)
Need to be committed to hearing what the user is really saying
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29. Study Similar or Competing Products
Incorporate features you like
Don’t just do something because your competitor does
May not be anything similar
Borrow ideas from other areas
Run usability studies on competitors' products
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30. Unsolicited User Comments
Effective when updating an existing product
Keep track of frequency of comments
Information that is readily available
Internet comments
Suggestions fostered by offering incentives
User hotline conversations
Don’t believe everything users say
Confirm usefulness of suggestions with other techniques
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31. Best Solution Best solution is to employ a variety of methods
Questionnaires and Interviews
Observational studies
Examination of competing, or similar products
Unsolicited user input
March 14th, 2011

32. What’s Up Next? Chapter 12 (12.6-12.12) Introduce Project Draft Plan
GOMS, KLM
Come up with questions and comments
Introduce Project Draft Plan
Introduce Task Analysis Lab
March 14th, 2011