1. Introduction to Usability Engineering
CS 352
Winter 2018
Elevator photo: Taken Fall 2014 at Phoenix Renaissance Hotel (The Grace Hopper Conference).

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

3. 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
In order to do that we must determine..

4. 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
There are lots of synonyms for it!
We also see it in a variety of fields.
Usability engr is an important area that shows up in many fields.

5. 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.
Execution: goal in your head and actually succeeded in doing it. (knowing how to do it)
Very confusing to thread film.
Evaluation: knowing whether or not you got it wrong. (being able to tell that you did it)
Learning a lot about the two gulfs and how to avoid users falling in to them.

6. Goals of Usability Engineering
(See Rogers handout, ch. 1):
effectiveness at task
eg, the nurses
safety
eg, privacy, losing work, mistakes that endanger
utility
learnability
memorability
efficiency
differences among last 3
Effectiveness: Tell the story of the nurses…
Observed people using software in the real world.
New software installed for nurses. It required them to turn their backs to the patients. Trying to establish a rapport, but turning your back?
He thought the answer was to train the nurses.
The goal is to help people be effective with their task, not to help people conform to the software.
Utility: the actual useful ness
Learnability: learn how to use it quickly – walk up and use interfaces, first time user
Memorability: remember how to use it, for the occasional user
Efficiency: have it be something you can use quickly to get the job done --system being used everyday, for all users.
All diff aspects of usability, sometimes in conflict with each other.
Which of these is more important to the software your trying to make more usable?
Could compare these attributes on both versions of the dial.
* Top one: What is it, how do you think it works?
Is supposed to represent a phone dial, but it doesn’t “dial” – instead, the numbers are buttons, not really a rotary.
What does this say about learnability, memorability, efficiency?
Is this efficient? No. Phone companies arranged them differently. Numbers are now much closer together. Less error as well probably.
Bottom one: its a click wheel. The buttons are (probably) back to beg, skip to end, and backspace/delete.
A little hard to figure out what these things are. Depends what its tied to, whether rewinding is a clear action you should be able to do.
Learnability is high, only a few actions, will learn quickly.

7. Design Principles: (Some tools for achieving goals)
Visibility of user’s options/actions.
WHAT options/actions available.
Feedback
Constrain
(making certain errors impossible)
eg: menus vs typing to prevent syntax errors.
(Internal) consistency
Affordance
makes clear HOW I can operate an object
Important for assignment!
Make a Big Deal about Internal consistency vs. External consistency.
Feedback: possible to tell if the action was useful
Internal consistency: is consistency of one part of the application with another part of that SAME application. 
Like if “purple” means “warning” in one part of the application, then it always means “warning” in all parts of that application.
Internal is most often an issues when you're designing your own interface. External consistency: is consistency with other applications. 
Like graying out menu items that aren’t available to the user is consistent with other common applications (e.g., with Canvas, with Microsoft Word, etc.)
Affordance: clear that I can click on all these images. (e.g. buttons or scroll bars, even a door)

8. HW #1: Design Principles
Pairs for this assignment.
Assign pairs!

9. 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.
Process activities:
Things you do as part of the usability engineering process.
We will be using the PRICPE design process you’ll hear about in a lecture soon.

10. 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.
Some think its towards the end like an evaluation step.
Can’t be done this way!
Interaction design should be integrated through the entire software process.
From the perspective of the people not the data or the computing.
What will they need for it to (be efficient, usable, and useful) following the attributes we may need such as efficiency, learnability, memorability and so on.
To evaluate its usability.

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

12. 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.
Ubiquitous: computing is all around you.
Ex: smart home.
Say you need to learn a new language, and you want to practice the language, so your tv changes language.
Computing that comes together for a common goal.
Start the reading, and homework.
Meet and greet each other!