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User Centred Design and
Low-Fidelity Prototyping
Human-computer Interaction
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User Centered Design
Design is based upon a user’s :
Abilities and real needs
Context
Work
Tasks
Golden rule of interface design KNOW
THE USER
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User Centered Design
A UCD is based on understanding the domain
of work or play in which people are engaged
and in which they interact with computers,
and programming computers to facilitate
human action….
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User Centered Design
Three assumptions:
The result of a good design is satisfied customer
The process of design is collaboration between
designers and customers: the design evolves and
adapts to their changing concerns
The customer and designer are in constant
communication during the entire process
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User Centered Design
This participatory design has some problems:
Intuitions wrong
Interview not precise
Designers can not know the user sufficiently well to
answer all issues that come up during the design.
Solution:
Designers should have access to pool of
representative users: End users, not their managers.
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Methods for involving the user
User : uses system after deployment
Tester: tests system after development,
before deployment
Informant: help during development
( interview, observations…)
Design partner : equal partner.
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Prototyping
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Why Do We Prototype?
Get feedback on our design faster (which
saves money)
Fix problems before code is written
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Fidelity in Prototyping
Fidelity refers to the level of detail
High fidelity?
prototypes look like the final product
Low fidelity?
Interfaces with many details missing
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Types of low-fi Prototypes
Paper
“Low fidelity prototyping”
Often surprisingly effective
Experimenter plays the computer
Implemented Prototype
Visual Basic
PowerPoint
Web tools (even for non-web UIs)
Html
Scripting
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Paper prototyping
Main idea:
Sketch out prototypes of the interface on paper
Potential users “walk through” task scenarios using the
paper interface
A designer “plays computer”
Change the design on-the-fly if helpful
Widely practiced in industry
Sounds silly at first, but is surprisingly effective
Helps people work together on the design
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The Materials
Large, heavy, white paper (11 x 17)
5x8 in. index cards
Post-it notes
Tape, stick glue, correction tape
Pens & markers (many colors & sizes)
Transparencies (including colored)
Colorforms (toy stores)
Scissors, X-acto knives, etc.
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Constructing the Model
Set a deadline
don’t think too long - build it!
Draw a window frame on large paper
Put different screen regions on cards
anything that moves, changes, appears/disappears
Ready response for any user action
e.g., have those pull-down menus already made
Use photocopier to make many versions
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Preparing for a Test
Select your participants
understand background of intended users
use a questionnaire
don’t use friends or family
Prepare scenarios that are
typical of the product during actual use
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Conducting a Test
Three or Four testers (preferable)
greeter : puts users at ease & gets data, gets forms
filled, assure confidentiality…..
facilitator : only team member who speaks
gives instructions & encourages thoughts, opinions
computer: knows application logic & controls it
always simulates the response, w/o explanation
observer(s) : take notes & recommendations
Typical session is approximately 1 hour
(preparing, testing, debriefing)
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Evaluating Results
Create a written report on findings
gives agenda for meeting on design changes
Make changes & iterate
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Advantages of Low-fi Prototyping
Takes only a few hours
no expensive equipment needed
Can test multiple alternatives
Can change the design as you test
Allows designers to work together
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Example of paper
prototyping
We will use the rule we underlined in
constructing the model (Use photocopier to
make many versions)
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Telebears example: Welcome, Registration time
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Telebears example: Welcome, Not Registration time
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Designing a content page
Using low-fi techniques
Card sorting
Idea from Peter Merholtz
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Designing a content page
Using low-fi techniques
Start with a page with all the features you
might want
Cut it up into pieces
Have people arrange the components
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Card sorting
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Low-fi Storyboards
Where do storyboards come from?
Film & animation
Give you a “script” of important events
leave out the details
concentrate on the important interactions
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Site map:
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Sketch example:
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Implemented prototypes
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Wizard of Oz
Technique
Faking the interaction.
The term is from the film “The Wizard of OZ”
“the man behind the curtain”
Main idea:
The participant interacts with a computer interface as
usual
Instead of the program writing back, a person writes back
pretending to be the computer
Very useful for assessing hard-to-implement features
Speech & handwriting recognition interface design
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pen-based interaction
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DENIM:
Designing Web Sites by Sketching
An Informal Tool For Early
Stage Web Site and UI
Design (you can download it from http://
dub.washington.edu/denim/)
Integrates multiple views
site map – storyboard – page
sketch
Supports informal interaction
sketching, pen-based
interaction
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DENIM example:
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Designing Interfaces with Denim
1) Designer sketches ideas rapidly with
electronic pad and pen
recognizes widgets
easy editing with gestures
2) Designer or end-user tests interface
widgets behave
specify additional behavior visually
3) Automatically transforms to a “finished” UI
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Specifying Behaviors
Storyboards
series of rough sketches depicting changes in
response to end-user interaction
Expresses many common behaviors
before after
Sequencing behavior between widgets
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Denim Storyboards
Copy sketches to storyboard window
Draw arrows from objects to screens
Switch to run mode to test
Denim changes screens on mouse clicks
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The SILK System
Integrate pen-based and electronic sketching
Support whole design cycle
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The SILK System
unlike a paper sketch, this electronic sketch is
interactive and can easily be annotated and
modified using editing gestures.
SILK allows the designer to extend the
interactivity of the recognized widgets using
storyboards
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SILK interface
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SILK Vs. DENIM
There are several key differences between
DENIM and SILK:
DENIM supports more views of the design (e.g.
site map) than SILK and integrates those views
through zooming.
SILK recognizes widgets that are sketched by the
designer. DENIM does not (yet).
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Prototyping Assignment:
Create a storyboard for a login page
Create a sketch for an plane ticket booking
page.
(use paper prototypes, no softwares)