1. Introduction to Usability Engineering
CS 352
Elevator photo: I took it Fall 2014 at Phoenix Renaissance Hotel (I was at the Grace Hopper Conference).

2. Logistics: CS352
Syllabus:
Go thru the syllabus with the students.

3. To the meat of the matter…

4. What is Usability Engineering?
Usability Engineering is the process of Methodically designing systems which are
Useful
Usable
Which includes
Determining what is useful
Determining what is usable
Evaluating these two factors empirically

5. Usability by Other Names in Other Fields
Usability Engineering
Human-computer interaction
Ergonomics
Interaction Design
User-interface design
User-centered design
Informatics/information systems/library science
Psychology/cognitive science
Ergonomics
Industrial engineering/design
Architecture
Art
Social sciences

6. Why bother with usability engineering?
Most software is supposed to help people be productive.
Build better software.
Help people like it enough to buy it (keep your job!).
Avoid fatal flaws in software, like Norman’s 2 gulfs:
Gulf of execution
Gulf of evaluation
Film projector, circa 1940s-1960s – to discuss the Gulfs.

7. Goals of Usability Engineering
(See Rogers handout, ch. 1):
effectiveness at task
eg, the nurses
safety
eg, privacy, losing work, mistakes that endanger
T&T#19, T&T #20
utility
learnability
memorability
efficiency
differences among last 3
effectiveness: tell the story of the nurses.
differences: learnability is for first-time user, memorability is for occasional user, efficiency is for all users (but esp those who use it everyday).
could compare these attributes on both versions of the dial.
UIs and Gulfs -- Don’t tell them the following – make them guess!
Top one: The numbers are clickable, it’s not really a rotary..
Bottom one: its a click wheel. The buttons are (probably) back to beg, skip to end, and play.
compare potential gulfs w these 2 interfaces.

8. Design Principles: (Some tools for achieving goals)
Visibility of user’s options/actions.
WHAT options/actions available.
Feedback
Constrain
(making some errors impossible)
eg: menus vs typing to prevent syntax errors.
(Internal) consistency
Affordance
makes clear HOW I can operate an object
widgets are for talking about most of these points.
Make a Big Deal about Internal consistency vs. External consistency.

9. HW #1: Design Principles
Pairs for this assignment.

10. How to do interaction design/usability engineering
Process (generally)
Identify needs/requirements
of the user experience.
Develop many alternative design ideas
that meet the requirements.
Mock-up and later build versions of the designs
to communicate/evaluate.
Evaluate
throughout the process.
PRICPE will guide us thru these.

11. When to do interaction design
At beginning of software project:
to help establish needs/requirements correctly in the first place
During design/implementation:
to continuously evaluate/monitor
During testing.
to evaluate.

12. Where do we go next? ? User Productivity Time Touch/voice WIMP
(Windows)
User Productivity
Command Line
Batch
1940s – 1950s
1960s – 1970s
1980s - Present
2000s-present
Time

13. Examples of new paradigms
Mobile computing
Wearable computing
Tangible computing
Ubiquitous computing
and many more….
Tangible:
Computing where you have to manipulate physical object you have in front of you.
Interface captures the movement.