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Defining Your Domain: User / Task / Environmental Analysis
HCC 729, 2/6/14
In-class Homework Critiques
Choose domain and partner for project…
Anatomy of a successful project
PGF Website RedesignAnalysis of Current Site and Proposed Prototypes for the
Potters’ Guild of Frederick
Week 2
Week 3
Week 3
Week 4
Week 4
Week 5
Week 6
Week 7
Wordpress Questions / Help?
Discussion
Inspirations or UI news?Readings
User / Task / Environmental Analysis
User Analysis
Why do you need to know your user?
Why perform user analysis?
• Design / build systems that meet user needs• Attract new / keep current customers (or
users)• Reduce development and maintenance costs• Discover new human behaviors / trends• Discover new user subgroups• …
A brief list of user characteristics
• Age• Gender• Culture• Language• Ability• Education (reading level)• Experience• …. Other examples?
User characteristics: physical differences
• Age (use larger fonts for older people)• Sex (consider your target group: e.g., more
women than men buy lipstick)• Vision limitations, such as color blindness• Other physical limitations that might restrict
movement (See Chapter 12)• Small children don’t have good fine-muscle
control: see big buttons on next slide
User characteristics: tool preferences
• Do your users know drop-down menus? • Do they prefer mouse or keyboard? (Some
advanced users hate the mouse: it slows them down.)
• Do they know frames? Popup windows? Search?– You won’t believe how different new users are,
compared to you, until you watch them
User characteristics: knowledge of job • Is your site used daily on the job, or it is used at home for
recreation or a hobby?• Is there a specialized vocabulary?• If in an office, how does work on your site fit in with
other activities? Could your user answer that question?• Does your user do the same job all day? Bored?• If for personal use, what is the purpose?
• To inform• To entertain• To sell
User characteristics: application familiarity
• NoviceFaces a frightening unknown; timid, nervous, in no mood to explore your goodies
• Advanced BeginnerLess fear: knows basics; still impatient at having to learn how to do tasks.
• Competent Performer Can diagnose simple problems and can perform a complex series of tasks
• ExpertSmall group. Can diagnose complex problems. Has a mental model of the application. Not typical users.
User characteristics: primary and secondary users
• Primary user: the person who actively uses the site:Airline reservation clerkHelp desk staff
• Secondary user: the person being served by a primary user:Airline passengerCustomer who called the support line
Task Analysis
Task analysis describes what your users are doing.
Task Analysis Overview
Develop an understanding of your user’s life• What tasks they perform• Why they perform these tasks• How they perform them
Approach, notations and techniques
1. Task decomposition• Splitting task into (ordered) subtasks
2. Knowledge based techniques• List what what the user knows about the task and
how it is organized• List all objects and actions involved in the task, and
then build taxonomies of them
3. Entity/object based analysis• Relationships between objects, actions and the
people who perform them• Won’t cover this today (Section 15.5 of reading)
When making your own TA…
• What is the main goal you are trying to support?• What data do you have to indicate this is
important to users?• What are the sub goals you want to support?• Which are most important to your stakeholders?• Which does your prototype implement?
• List these goals and sub goals, and then try making a TA to describe your system.
Two Types of Task Decomposition
• Hierarchical Task Analysis (HTA) – descriptions of information requirements for lowest level sub-operations including a dictionary of objects and associated actions
• Cognitive Task Analysis (CTA) – Includes cognitive characteristics of task space (e.g. cognitive load, response time, cognitive processing, display interpretation). – Will not be focusing on CTA in this class
Hierarchical Task Analysis
Hierarchical Task Analysis• Decompose tasks to express a structure• Describe an activity in terms of:
• tasks, subtasks, and plans• order things are completed• the conditions subtasks are performed
• Useful for decomposing complex tasks• Has a narrow view of the task
Types of Hierarchical Task AnalysisTextual HTA Diagrammatic HTA
HTA Terms
• Task / Sub-task• Objects – things used in the task• Actions - performed• Goal / Sub-goal• Plan – steps taken to reach goal
Hierarchical Task Analysis Example
Let’s describe how you make tea in a pot (not a microwave)
What are the steps to make tea?
Kettle Pot
Domain specific knowledge…
Top-Level Tea Tasks
Task 0. Make a cup of tea1. Boil water in kettle2. Empty old water in pot (if any)3. Make pot of tea4. Wait 4-5 minutes5. Pour tea
Tea Plan
Task 0. Make a cup of tea1. Boil water in kettle2. Empty old water in pot (if any)3. Make pot of tea4. Wait 4-5 minutes5. Pour tea Plan 0 for Task 0.
A.Do 1B. While A, if pot is full,
do 2C.Then do 3 and 4D.After 5 min do 5
Put tea leaves in potPour in hot water
Tea Plan
Task 0. Make a cup of tea1. Boil water in kettle2. Empty old water in pot (if any)3. Make pot of tea4. Wait 4-5 minutes5. Pour tea Plan 0 for Task 0.
A.Do 1B. While A, if pot is full,
do 2C.Then do 3 and 4D.After 5 min do 5
But what does this entail?
Tea Plan
Task 0. Make a cup of tea1. Boil water in kettle2. Empty old water in pot (if any)3. Put Leaves in pot4. Pour in hot water5. Wait 4-5 minutes6. Pour tea
Plan 0 for Task 0. A.Do 1B. While A, if pot is full,
do 2C.Then do 3 - 5D.After 5 min do 6
But is this good enough?
• Now that we have our first HTA, we ask “What have we missed or gotten wrong?”
• Ask experts to look at our HTA, but do they have expert blindspots?
• We can examine subtasks and think about them in context of whole system.– 1.4 says turn off gas, but did we ever turn it on?
Types of plans
• sequence 1.1 then 1.2 then 1.3• optional if the pot is full 2• wait when kettle boils, do 1.4• cycles do 5.1 5.2 while there are still empty
cups• parallel do 1; at the same time …• discretionary do any of 1.3.1, 1.3.2 or 1.3.3 in
any order
When do you stop?
• How many subtasks should you include?• P X C Rule– Multiply probability that the user will make a mistake
in the task by the cost of the mistake. – Stop adding subtasks if this is below a threshold– Only expand important or critical tasks
• Stop when you can’t easily describe subtasks– Internal decision making or motor responses
• Stop when you have fully described the situation
Knowledge-Based Analysis
KBA – How to start
• List all objects and actions involved in the task
• Build taxonomies (groups) of all objects and actions
• Work with target user to define / organize groups so you capture their knowledge
KBA example
How do you create taxonomies?• Card sorting with an
expert / target user
• Organize things into similar piles on paper.
• Name the pile• Split it into 2 piles• Make it more explicit
• What if it spans multiple categories?
TAKD and TDH• Task analysis for knowledge description (TAKD)
uses Task Descriptive Hierarchies(TDH) to handle branching:• XOR — object in exactly one branch• AND — object must be in both• OR — can be in one, many or none
TDH example
• A plate may be used for preparation or dining
Why is this useful?
Uses for Task Analysis
• Requirements capture and systems design• changes focus from system to user• suggests candidates for automation, or optimization• uncovers user's conceptual model
• Interface design• Identify incorrect information or assumptions• Identify missing information• Identify when user has incomplete knowledge of task
or goal• Identify when there is insufficient or delayed feedback
Uses for Task Analysis• Create system requirements or charts
– Think about design in terms of tasks and goals
• Create ‘How to’ manuals– Doesn’t require conceptual knowledge– Ideal for novices
• Limitations– Assumes all tasks have been identified– Doesn’t explain why we do something
To make cups of tea
boil water –– see page 2empty potmake pot –– see page 3wait 4 or 5 minutespour tea –– see page 4
–– page 1 ––
Make pot of tea
warm potput tea leaves in potpour in boiling water
–– page 3 ––
once water has boiled
Uses for Task Analysis• Assistive Technology:
breaking down tasks crucial to daily living– How to brush teeth– How to call 911– How to make a salad
• Who might benefit from this?
How to Brush Your Teeth1. Get toothbrush2. Get toothpaste3. Turn on cold water4. Run toothbrush under water5. Remove cap from toothpaste6. Place cap on rim of basin7. Apply toothpaste to toothbrush8. Brush9. Spit10. Rinse toothbrush11. Fill cup with water12. Rinse mouth13. Spit14. Turn off water15. Put cap on toothpaste16. Put toothpaste away17. Put toothbrush away
Environmental Analysis
Give the user a place to do their task
Why does knowing the environment matter?
Environment Analysis
• Where do people use your interface? Many variations:– An outdoor ATM in a cold location where people wear gloves
while using it (need huge buttons)– On a combination cell phone/wireless browser, with a tiny
display (need tiny fingers!)– In a location where direct sun can hit your display, making it
hard to read– In an extremely noisy factory, where any sound you add would
be impossible to understand– In an office that is quiet and dull
• May be worth wile to observe your users in their own setting to fully understand their environment
Putting it all together: Personas
A nice way to make sense of your user, task and environmental Analysis
Making sense of your data: Personas
• Identify trends and similarities in your data – User analysis: who are the users?– Task Analysis: what do they do? How do they use
existing technology?– Environmental analysis: in what contexts do they
live/play/work? Where do they use the technology now?
Making sense of your data: Personas
• Group these trends and identify themes• Form fictional personas– Fictional individual who conveys several of the
trends you found in the data• Capture and present these personas in a way
that clearly illustrate the differences across personas
Example Personas
• Research personas created to understand elders’ relationship to technology in the home by Francine Gemperle.
Capture some of the variety of character and lifestyle, health and living arrangement
Data was gathered from multiple interviews and visits to elders homes.
In-class Exercise
Practice building persona and task analysis
Work in groups of 3
Users: UMBC HCC Students
• Co-create personas that describe 2 people in your group• Choose the two people by thinking about how
they might be differ when approaching the task• Personas should simply focus on these
differences
Tasks
• Create either a HTA for one of these users checking their email.• You can either create a textual or hierarchical
HTA
For next week
AssignmentReadings
Understanding your project domain
• Conduct a user/environmental/task analysis for the website you are redesigning• User analysis: write 100 -200 words describing the
population who uses this site• Identify 5 tasks that they would want to do on this site
(a list is fine)• Create an HTA (either text or hierarchical) for one of these
tasks
• Environmental analysis: write 75-100 words describing the environment where this site will be used and the impact it will have on the redesign.
Understanding your project domain
• Using all of the information from your project domain, create 2 personas (4 if in a group) of people who would use this site based on what you have learned about it. Each persona should describe details about this individual that are relevant to tasks they are interested in accomplishing on this site. • Each persona should be 100-200 words• Include an image of for each persona (borrowing
internet photos is fine)
Making your own TA
• What is the main goal you are trying to support?– What data do you have to indicate this is important to
users?• What are the sub goals you are trying to support?– Which are most important to your stakeholders?– Which does your prototype implement?
• List these goals and sub goals, and then try making an HTA to describe your system.
• All of this goes on your blog
Readings (Heuristic Evaluation)
• Required• Usability Engineering §1.4, §4.9 and §511.
In particular, Nielsen’s list of 10 heuristics on page 20
• Optional• Usability Engineering, Chapter 5• Nielsen’s Tech transfer of heuristic evaluation and usability
inspectionhttp://www.nngroup.com/articles/technology-transfer-of-heuristic-evaluation/
• Nielsen’s on-line heuristicshttp://www.useit.com/papers/heuristic/heuristic_list.html
• Nielsen’s severity ratingshttp://www.useit.com/papers/heuristic/severityrating.html