CS 485/515General course outline

• Design for people – theory and vocabulary• Just enough psychology• Task-centered procedure for user interface

design.• Tools for user interface design• Application to your own projects

– Initial design and cognitive walkthroughs– Iterative design and user tests

• Advance User Interface topics and techniques

URL: crl.nmsu.edu/~ogden/cs485

Today’s theme

• It’s obvious…• (Or: It is easy when you know how)

Which is more obvious?

2004

2007

2008

2009

2010

Is UI design easy or hard?Does it really matter?

• Even simple decisions require thought and are influenced by experience

• Al Gore – George Bush election determined by UI design.

• It is easy to blame the user.

Same or different?

A AA A

A a

A A

A B

Even simple decisions require thought and depend on context

Did the user (voter) see the arrow?How do you know?

Florida Butteryfly Ballot

19,120 ballots in West Palm Beach were disqualified/nullified because of double voting.

Margin of victory was 512 votes.

Sample ballot looks easier when the holes are missing.

Sample Ballot

Presidential page is different from all other ballots.

Linear Visual Search

Numeric Mapping

http://danbricklin.com/log/ballotusability.htm

Today’s theme (restated)

• Expectations influence perceptions (aka “It’s obvious”)

• The Cow example shows us:– The more you know the less likely you will be able to

judge what others may know.– What you ‘know’ influences what you ‘see’– You can’t judge a user interface by just looking at it.

Remember the cow

Today’s questions

• What is an interface?• What is a good interface?

Push or Pull ?

“Designer”Door

Good and bad design

• What is wrong with the Apex remote?

• Why is the TiVo remote so much better designed?– Peanut shaped to fit in

hand– Logical layout and

color-coded, distinctive buttons

– Easy to locate buttons

What is a good interface?• There is no such thing

– cf. Good furniture arrangement

• The test of quality depends on it’s context– How will the software be used? Who will use it? How

long?– How important is: Learnability? Portability? ...

• The answers vary for each application• Finding the answers is the first step in UI design• Depends on users and tasks. So we must learn

a process for figuring it out.