Usability testing

IS 403: User Interface DesignShaun Kane

Today• Testing our prototypes, to fix usability bugs

and make them better

“Discount usability engineering”

• Jakob Nielsen– http://www.nngroup.com/articles/guerrilla-hci/

• Scenarios• Think aloud• Heuristic evaluation

http://www.nngroup.com/articles/guerrilla-hci/

Goals of usability testing• See what our users’ expectations are

• Learn how our users think about solving a problem– Remember, we are not our users

• Identify confusing points in the interface

What usability testing won’t do

• Tell us how to fix it– Users don’t always know what they want– BUT, may identify new things to test

• Tell us how it will work in the real world

Your main goal• Find problems! (there

definitely are some)

• If you are not finding problems:– You might be guiding users

too much– You might be providing too

vague tasks– Your app might not do

anything interesting

How to do it• Clearly defined tasks

– Bad: Search for a shoe– Good: Search for a basketball sneaker in your

size as a treat for yourself

• Let users explore, make mistakes (don’t help them)

• Think aloud

How to do it• Iterate: Better to test 3, revise, test 3 more

than test 6 at once

Thinking aloud• Essential to good usability testing

• Allows you to see what’s going on in the user’s head– Without interrupting them– Without requiring them to recall what they were

thinking

• May take some practice, reminders, or a demonstration from you

Benefits of think aloud• Cheap and easy to run• Robust to mistakes• Flexible for different fideilty prototypes,

testing contexts• Convincing – good support for design

changes• Easy to learn

Drawbacks• Unnatural situation• Filtered statements – users censor

themselves in think aloud• Possible to bias users with leading

questions or behavior• Not enough alone – you still need

heuristic evaluation, design iteration

Live demo

let’s buy some shoes

Taking notes• Try to identify usability problems (or

potential future problems)

• Some examples:– User can’t find something– User misunderstands some label or button– Can’t get there from here– User performs step in unexpected order– User gets confused or loses their place

Writing up your notes• Organize by task or site area,

rather than by user– Problems experienced by >1 user are especially

important!

• Make sure to note– Task the user is trying to perform– What actually happened– Your interpretation of the problem– Relevant comments from think-aloud– Later: Design suggestions

http://www.indiana.edu/~usable/reports/acc_report.pdf

http://www.indiana.edu/~usable/reports/acc_report.pdf

http://www.scribd.com/doc/92602002/Yelp-Usability-Test-Report-FINAL

Let’s get some practice• Pair up with someone• Let’s test our A6 prototypes• 10 minutes per person• Take notes and report back