Introduction to Usability Engineering

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Introduction to Usability Engineering

• CS 352
• Winter 2008

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Assumptions

• You should be very familiar with the following
  concepts and practices
• Graphical User Interfaces (GUIs)
• Basics of Programming, some VB or HTML
• Basics of some graphics manipulation package
• This is a 300-level class, I expect you to be
  responsible and keep up with the reading and
  complete your assigned work on time. Lectures
  will not cover all reading, I will focus on
  explaining material which is particularly
  difficult, or which is not well-explained in the
  book. You are still responsible for all materials
  for exams and your work.

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What do you expect from this class?
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What is Usability Engineering?

• Different from
• Human-computer Interaction?
• User Interface Design?
• Interaction Design?
• User-centered design?
• Software Engineering?

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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 system usability

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What is Human-Computer Interaction?

• Human-computer interaction (HCI) is
• concerned with the design, evaluation and
  implementation of interactive computing systems
  for human use and with the study of major
  phenomena surrounding them (ACM SIGCHI, 1992,
  p.6)

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What is wrong with being design centered?

• Design
• Science?
• Art?
• Puts focus on the artifact rather than the
  process and evaluation aspects

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Why bother with usability engineering?

• Computers affect most people
• 89 of US has access to computers, 65 are online
  
• Have to deal with businesses government
  agencies
• Computers are everywhere!!! (help!)
• Not just white boxes
• Success often depends on ease of use, not power
  or features
• Learning to use a computer system is like
  learning to use a parachute if a person fails
  on the first try, odds are he wont try again.
  anonymous

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Goals of Usability Engineering

• Nielsen
• Increase learnability
• Increase efficiency
• Increase memorability
• Decrease errors
• Increase satisfaction
• Preece
• Utility ?
• Effectiveness ?

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Usability as a Process

• Nielsen
• Identify who the users are
• Understand their activities
• Understand the context in which these take place
• Applying design principles and design techniques,
  like
• Scenarios
• Think-aloud protocols
• Heuristic Evaluation

• Preece
• Taking into account what people are good and bad
  at
• Considering what might help people with the way
  they currently do things
• Thinking through what might provide quality user
  experiences
• Listening to what people want and getting them
  involved in the process
• Using tried and tested user-based techniques
  during design process

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HCI by Other Names in Other Fields

• Usability Engineering
• Human-computer interaction
• Computer-human interaction
• Human-machine 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

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Historical Perspective
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• Why?
• Get a sense of where we are
• Things havent always been this way, wont always
  stay this way, computers and interaction evolving
• Understand lessons from history
• Understand why we are here
• Avoid repeating same mistakes

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History of computer interaction
?
WIMP (Windows)
User Adoption (not productivity!)
Command Line
Batch
M
B
K
?
1940s 1950s
1980s - Present
1960s 1970s
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History of computer interaction
?
WIMP (Windows)
User Adoption (not productivity!)
Command Line
Educated
Batch
Professionals
Experts
?
1940s 1950s
1980s - Present
1960s 1970s
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Eniac (1943)

• A general view of the ENIAC, the world's first
  all electronic numerical integrator and computer.

From IBM Archives.
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Mark I (1944)

• The Mark I paper tape readers.

From Harvard University Cruft Photo Laboratory.
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Stretch (1961)

• A close-up of the Stretch technical control
  panel.

From IBM Archives.
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Batch Processing

• Computer performed one task at a time
• No interaction once computation started
• Switches, wires, punch cards and tapes for I/O
• Very limited, highly trained group of operators

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Command Line (Mid 1960s)

• Computers hit big business
• More varied tasks text processing, editing,
  email etc
• Need for interactivity
• Used by secretaries, salesmen, accountants, CS
  students etc
• Reduced training

Need for HCI
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The Ubiquitous ASR 33 Teletype

• ASR Automatic Send / Receive
• Save programs on punched paper tape
• The first direct human-computer interface
  experience for many in the 1960s
• About 10 characters per second - 110 bps

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The Ubiquitous Glass Teletype

• 24 x 80 characters
• Up to 19,200 bps (Wow - was big stuff!)

Source http//www.columbia.edu/acis/history/vt100
.html
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Where we are now WIMP / GUI

• Computers in the home, for everyday tasks, no
  training
• From multi-user to multitasking systems
• Windows, Icons, Menus, Pointers
• Graphical User Interface
• WIMP interface allows you to do several things
  simultaneously
• Has become the familiar GUI interface

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Innovator Ivan Sutherland

• SketchPad - 1963 PhD thesis at MIT
• Hierarchy - pictures subpictures
• Master picture with instances (ie, OOP)
• Constraints
• Icons
• Copying
• Light pen input device
• Recursive operations

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Douglas Engelbart

• The Problem (early 50s)
• ...The world is getting more complex, and
  problems are getting more urgent. These must be
  dealt with collectively. However, human abilities
  to deal collectively with complex / urgent
  problems are not increasing as fast as these
  problems.
• If you could do something to improve human
  capability to deal with these problems, then
  you'd really contribute something basic.
• ...Doug Engelbart

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The First Mouse (1964)
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Xerox Star - 1981

• First commercial PC designed for business
  professionals
• desktop metaphor, pointing, WYSIWYG, high degree
  of consistency and simplicity
• First system based on usability engineering
• Paper prototyping and analysis
• Usability testing and iterative refinement

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Xerox Star Desktop
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Lessons form Xerox Star?

• Usability matters, usability sells
• Star flopped, but Mac succeeded
• Cost 15,000
• Lacked spreadsheet, standard business software
• Usability can be engineered
• Birth of HCI as a design discipline

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Paradigm Direct Manipulation

• 82 Shneiderman describes appeal of
  rapidly-developing graphically-based interaction
• object visibility
• incremental action and rapid feedback
• reversibility encourages exploration
• replace language with action
• syntactic correctness of all actions
• WYSIWYG, Apple Mac

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Paradigm Metaphor

• All use is problem-solving or learning to some
  extent
• Relating computing to real-world activity is
  effective learning mechanism
• File management on office desktop
• Financial analysis as spreadsheets
• The tension between literalism magic
• Eject disk or CD on Mac by dragging to trash can

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Evolution from Xerox Star?
1981
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Evolution from Xerox Star?
1981
1985
Windows 1.0
Mac OS 1.0
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Evolution from Xerox Star?
1981
1985
1987
Windows 1.0
Mac OS 1.0
Mac OS 5.0
Windows 2.0
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Evolution from Xerox Star?
1981
1985
1987
1992
Windows 1.0
Mac OS 1.0
Mac OS 5.0
Windows 3.0
Mac OS 7
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Evolution from Xerox Star?
1981
1985
1987
1992
1998
Windows 1.0
Mac OS 1.0
Mac OS 5.0
Windows 3.0
Mac OS 7
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Evolution from Xerox Star?
1981
1985
1987
1992
1998
2007
Windows 1.0
Mac OS 1.0
Mac OS 5.0
Windows 3.0
Mac OS 7
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Evolution from Xerox Star?
1981
1985
1987
1992
1998
2007
Windows 1.0
Mac OS 1.0
Mac OS 5.0
Windows 3.0
Mac OS 7
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The WIMP Plateau
?
WIMP (Windows)
User Productivity
Command Line
Batch
?
1980s - Present
1940s 1950s
1960s 1970s
Time
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Examples of new paradigms

• Ubiquitous computing
• Wearable computing
• Tangible bits, augmented reality
• Attentive environments
• Transparent computing
• and many more.

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Two examples BlueEyes (IBM) and Cooltown (HP)

• Visionary approaches for developing novel
  conceptual paradigms

Almalden.ibm.com/cs/blueeyes/ cooltown.hp.com/mpul
se/backissues/0601/0601-cooltown.asp