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Human
Computer Interaction
(CS408)
VU
Lecture
44
Lecture
44. Emerging
Paradigms
Learning
Goals
As the
aim of this lecture is to
introduce you the study of
Human Computer
Interaction,
so that after studying this
you will be able to:
· Understand
the role of information
architecture
· Understand
the importance of
accessibility
Metadata
A web
site is a collection of interconnected
systems with complex dependencies.
A
single
link on a page can simultaneously be
part of the site's
structure, organization,
labeling,
navigation, and searching
systems. It's useful to
study these systems
inde-
pendently,
but it's also crucial to
consider how they interact.
Reductionism will not
tell us
the whole truth.
Metadata
and controlled vocabularies present a
fascinating lens through
which to
view
the network of relationships
between systems. In many
large metadata-driven
web
sites, controlled vocabularies
have become the glue that
holds the systems
together.
A thesaurus on the back end
can enable a more seamless
and satisfying user
experience
on the front end.
In
addition, the practice of
thesaurus design can help
bridge the gap between
past and
present.
The first thesauri were
developed for libraries,
museums, and
government
agencies
long before the invention of
the World Wide Web. As
information architects
we can
draw upon these decades of
experience, but we can't copy
indiscriminately.
The
web sites and intranets we
design present new challenges
and demand creative
solutions.
When it
comes to definitions, metadata is a
slippery fish. Describing it as
"data about
data"
isn't very helpful. The
following excerpt from
Dictionary.com takes us 2 little
further:
In data
processing, meta-data is definitional data
that provides information
about or
documentation
of other data managed within an
application or environment.
For
example,
meta-data would document data about data
elements or attributes (name,
size, data
type, etc) and data
about records or data structures (length,
fields, columns,
etc)
and data about data (where it is
located, how it is associated,
ownership, etc.).
Meta-data
may include descriptive
information about the
context, quality and
condi¬tion,
or characteristics of the data.
While
these tautological explanations
could lead us into the
realms of epistemology
and
metaphysics, we won't go there.
Instead, let's focus on the
role that metadata
plays
in the
practical realm of information
architecture.
Metadata
tags are used to describe documents,
pages, images, software, video
and
audio
files, and other content
objects for the purposes of
improved navigation
and
retrieval.
The HTML keyword meta tag
used by many web sites
provides a simple
example.
Authors can freely enter
words and phrases that
describe the content.
These
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Computer Interaction
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keywords
are not displayed in the
interface, but are available
for use by search
engines.
<meta
name="keywords" content="information
architecture, content management,
knowledge
management, user
experience">
Many
companies today are using
metadata in more sophisticated ways.
Leveraging
content
management software and controlled
vocabularies, they create dynamic
meta
data-driven
web sites that support
distributed authoring and
powerful navigation.
This
metadata-driven
model represents a profound change in
how web sites are created
and
managed.
Instead of asking, "Where do I
place this document in the
taxaonomy?" we
can
now ask, "How do I describe this
document?" The software and
vocabulary
systems
take care of the
rest.
Controlled
Vocabularies
Vocabulary
control comes in many shapes
and sizes. At its most
vague, a controlled
vocabulary
is any defined subset of
natural language. At its
simplest, a controlled
vocabulary
is a list of equivalent terms in the
form of a synonym ring, or a
list of
preferred
terms in the form of an
authority file. Define
hierarchical relationships
between
terms (e.g., broader, narrower)
and you've got a
classification scheme.
Model
associative
relationships between concepts (e.g.,
see also, see related)
and
Since a
full-blown thesaurus integrates
all the relationships and
capabilities of the
simpler
forms, let's explore each of
these building blocks before
taking a close look at
the
"Swiss Army Knife" of
controlled vocabularies.
Classification
schemes can also be used in
the context of searching.
Yahoo! does this
very
effectively. Yahoo!'s search results
present "Category Matches,"
which
reinforces
users' familiarity with
Yahoo!'s classification
scheme.
Pel$:find
Hamsters in Yahoo! Pets
Bizarre
Humor> Hamster Dance
Humor>
Hamsters
Rodents>
Hamsters
List
"hamsters"_by location
The
above are Category Matches
at Yahoo!
The
important point here is that
classification schemes are
not tied to a single view
or
instance.
They can be used on both
the back end and
the front end in all
sorts of ways.
We'll
explore types of classification
schemes in more detail later
in this chapter, but
first
let's take a look at the
"Swiss Army Knife" of
vocabulary control, the
thesaurus.
Thesauri
Dictionary.com
defines thesaurus as a "book of
synonyms, often including
related and
contrasting
words and antonyms." This
usage harkens back to our
high school English
classes,
when we chose big words
from the thesaurus to impress
our teachers.
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Computer Interaction
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Our
species of thesaurus, the one
integrated within a web site
or intranet to improve
navigation
and retrieval, shares a
common heritage with the
familiar reference text
but
has a
different form and function.
Like the reference book,
our thesaurus is a semantic
network
of concepts, connecting words to their
synonyms, homonyms,
antonyms,
broader
and narrower terms, and
related terms.
However,
our thesaurus takes the form
of an online database, tightly
integrated with
the
user interface of a web site
or intranet. And while the
traditional thesaurus
helps
people go
from one word to many
words, our thesaurus does
the opposite. Its
most
important
goal is synonym management,
the mapping of many synonyms
or word
variants
onto one preferred term or
concept, so the ambiguities of
language don't
prevent
people from finding what
they need.
So, for
the purposes of this book, a
thesaurus is:
A
controlled vocabulary in which
equivalence, hierarchical, and
associative
relationships
are identified for purposes of
improved retrieval..
--ANSI/NISO
Z39.19 -1993 (R1998).
Guidelines for the
Construction, Format,
and
Management
of Monolingual Thesauri.
A
thesaurus builds upon the
constructs of the simpler controlled
vocabularies,
modeling
these three fundamental
types of semantic relationships.
Each
preferred term becomes the
center of its own semantic network.
The equivalence
relationship
is focused on synonym management.
The hierarchical
relationship
enables
the classification of preferred
terms into categories and subcategories.
The
associative
relationship provides for
meaningful connections that are
not handled by
the
hierarchical or equivalence
relationships. All three relationships
can be useful in
different
ways for the purposes of
information retrieval and
navigation.
44.1
Accessibility
Accessibility
is a general term used to describe
the degree to which a system is
usable
by as
many people as possible
without modification. It is not to be
confused with
usability
which is used to describe how
easily a thing can be used
by any type of user.
One
meaning of accessibility specifically
focuses on people with
disabilities and
their
use of
assistive devices such as screen-reading
web browsers or wheelchairs.
Other
meanings
are discussed below.
Accessibility
is strongly related to universal
design in that it is about
making things as
accessible
as possible to as wide a group of
people as possible. However,
products
marketed
as having benefited from a
Universal Design process are
often actually the
same
devices customized specifically
for use by people with
disabilities. It is rare to
find a
Universally Designed product at
the mass-market level that is
used mostly by
non-disabled
people.
The
disability rights movement advocates
equal access to social,
political and
economic
life which includes not
only physical access but
access to the same
tools,
organisations
and facilities which we all
pay for.
A typical
sign for wheelchair
accessibilityAccessibility is about
giving equal access
to
everyone.
While it
is often used to describe facilities or
amenities to assist people
with
disabilities,
as in "wheelchair accessible", the term
can extend to Braille
signage,
wheelchair
ramps, audio signals at pedestrian
crossings, walkway contours,
website
design,
and so on.
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Human
Computer Interaction
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Various
countries have legislation
requiring physical
accessibility:
In the
UK, the Disability Discrimination
Act 1995 has numerous
provisions for
accessibility.
In the
US, under the Americans
with Disabilities Act of
1990, new public and
private
business
construction generally must be accessible.
Existing private businesses
are
required
to increase the accessibility of their
facilities when making any
other
renovations
in proportion to the cost of
the other renovations. The
U.S. Access Board
is "A
Federal Agency Committed to
Accessible Design for People
with Disabilities."
Many
states in the US have their
own disability laws.
In
Ontario, Canada, the Ontarians
with Disabilities Act of
2001 is meant to
"improve
the
identification, removal and
prevention of barriers faced by
persons with
disabilities..."
Introduction to
Web Accessibility
Introduction
Most
people today can hardly
conceive of life without the
Internet. It provides
access
to
information, news, email, shopping,
and entertainment. The
Internet, with its
ability
to serve
out information at any hour
of the day or night about
practically any topic
conceivable,
has become a way of life for
an impatient, information-hungry
generation.
Some have argued that no
other single invention has
been more
revolutionary
since that of Gutenberg's original
printing press in the mid
1400s. Now,
at the
click of a mouse, the world
can be "at your
fingertips"--that is, if you
can use a
mouse...
and if you can see
the screen... and if you
can hear the audio--in
other
words, if
you don't have a disability
of any kind.
Before
focusing on the challenges
that people with
disabilities face when
trying to
access
web content, it makes more
sense to discuss the ways in
which the Internet
offers
incredible opportunities to people
with disabilities that were
never before
possible.
The web's potential for
people with disabilities is
truly remarkable.
The
Web Offers Unprecedented
Opportunities
The
Internet is one of the best
things that ever happened to
people with
disabilities.
You
may not have thought
about it that way, but
all you have to do is think
back to
the days
before the Internet was as
ubiquitous as it is today to see
why this is so.
For
example, without the
Internet, how did blind
people read newspapers? The
answer
is that
they mostly didn't. At best,
they could ask a family
member or friend to
read
the
newspaper to them. This method
works, but it makes blind
people dependent upon
others.
They could never read the
newspaper themselves. You might think
that
audiotapes
or Braille printouts of newspapers could
offer a reasonable solution,
but
both
options are expensive and
slow compared to the rate at
which publishers
create
and
distribute newspapers. Blind people
wouldn't receive the news
until after it was
no longer
new. Not only that,
but a Braille version of the
Sunday New York
Times
would be
so big and bulky with
the extra large and
thick Braille embossed paper
that
you'd
practically have to use a
forklift to move it around.
None of these methods of
reading
newspapers are ideal. They're too
slow, expensive, and too
dependent upon
other
people.
With
the advent of the World
Wide Web, many newspapers
now publish their
content
electronically
in a format that can be read by
text-to-speech synthesizer
software
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Human
Computer Interaction
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programs
(often called "screen readers")
used by the blind. These
software programs
read
text out loud so that
blind people can use
computers and access any
text content
through
the computer. Suddenly,
blind people don't have to
rely on the kindness
of
other
people to read the newspaper to them.
They don't have to wait
for expensive
audio
tapes or expensive, bulky
Braille printouts. They
simply open a web
browser
and
listen to their screen
reader as it reads the newspaper to
them, and they do it
when
they
want to do it. The Internet
affords a whole new level of
independence and
opportunity
to blind people. When you
understand the impact that
the Internet can
have in
the lives of blind people,
the concept of web accessibility takes on
a whole
new
level of significance.
Similarly,
people with motor
disabilities who cannot pick
up a newspaper or turn its
pages
can access online newspapers
through their computer,
using certain assistive
technologies
that adapt the computer
interface to their own
disabilities. Sometimes the
adaptations
are crude, such as having
the person place a stick in
the mouth, and to
use
that
stick to type keyboard commands. In
other cases, the adaptations
are more
sophisticated,
as in the use of eye-tracking
software that allows people
to use a
computer
with nothing more than
eye movements. People with
tremors may use a
special
keyboard with raised ridges
in-between the keys so that
they can place
their
hand
down on the keyboard and
then type the letters,
rather than risk typing
the wrong
keys.
Most of these people would
not be able to use a mouse
with much accuracy.
Regardless of
the level of sophistication,
many of these adaptations
have one thing in
common:
they make use of the
keyboard, or emulate the use
of a keyboard, rather
than
the use of a mouse. As with
people who are blind,
the Internet allows people
with
motor
disabilities to access information in
ways that they never
could before.
People
who are deaf always had
the possibility of reading newspapers on
their own,
so it may
seem that the Internet
does not offer the
same type of emancipation
that it
does to
those who are blind or to those
with motor disabilities, but
there are a few
cases in
which the Internet can
still have a large impact.
For example, they can
read
online
transcripts of important speeches, or
view multimedia content that
has been
fully
captioned.
Falling
Short of the Web's
Potential
Despite
the Web's great potential
for people with
disabilities, this potential is
still
largely
unrealized. Where can you
find web-based video or multimedia
content that
has been
fully captioned for the
deaf? What if the Internet
content is only
accessible
by using
a mouse? What do people do if
they can't use a mouse?
And what if web
developers
use all graphics instead of
text? If screen readers can
only read text,
how
would
they read the graphics to
people who are blind? As soon as
you start asking
these
types of questions, you
begin to see that there
are a few potential glitches
in the
accessibility
of the Internet to people
with disabilities. The
Internet has the
potential
to
revolutionize disability access to
information, but if we're
not careful, we can
place
obstacles
along the way that
destroy that potential, and
which leave people
with
disabilities
just as discouraged and
dependent upon others as
before.
People
with Disabilities on the
Web
Though
estimates vary, most studies find that
about one fifth (20%) of
the population
has
some kind of disability. Not
all of these people have
disabilities that make
it
difficult
for them to access the
Internet. For example, a person whose
legs are
paralyzed
can still navigate a web
site without any
disability-related difficulty. Still,
if
only
half--or even a quarter--of
these individuals have
disabilities that affect
their
ability
to access the Internet, this
is a significant portion of the
population. Businesses
would be
unwise to purposely exclude
20, 10 or even 5 percent of
their potential
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customers
from their Web sites.
Schools, universities, and government
entities would
be not
only unwise, but, in many
countries, they would also
be breaking the law
if
they
did so.
Each of
the major categories of disabilities
require certain types of
adaptations in the
design of
the web content. Most of
the time, these adaptations
benefit nearly
everyone,
not just people with
disabilities. For example,
people with cognitive
disabilities
benefit from illustrations
and graphics, as well as
from properly-organized
content
with headings, lists, and
visual cues in the
navigation. Similarly,
though
captioned
video content is meant to
benefit people who are deaf,
it can also benefit
those who
do not have sound on their
computers, or who do not want to
turn the
sound on
in public places such as
libraries, airplanes, or computer
labs.
Occasionally,
Web developers must implement
accommodations that are
more
specific
to people with disabilities.
For example, developers can
add links that
allow
blind
users or people with motor
disabilities who cannot use
a mouse to skip past
the
navigational
links at the top of the
page. People without disabilities
may choose to use
this
feature as well, but they
will usually ignore it. In
almost every case, even
these
disability-specific
adaptations can be integrated
into the site's design
with little or no
impact to
its overall visual "look
and feel." Unfortunately,
too many web
developers
are
convinced that the opposite
is true. They worry that
their sites will become
less
appealing
to their larger audience of
people without disabilities.
This faulty
perception
has
led to countless circular debates,
that tend to cause
unnecessary friction
between
web
designers and people with
disabilities.
From
the perspective of people
with disabilities, inaccessible web
content is an
obstacle
that prevents them from
participating fully in the
information revolution
that
has
begun unfolding on the
Internet. To them, it is a matter of
basic human rights.
When
web developers truly
understand this perspective, most of
them realize the
importance
of the issue, and are
willing to do what they can
to make their Web
content
more accessible.
Comprehensive
Solutions
There
are two key components to
any effort to achieve web
accessibility:
· Commitment
and accountability
· Training
and technical support
Either of
these by itself is
insufficient.
Commitment
and accountability
Awareness.
The foundation of any kind
of commitment to web accessibility
is
awareness
of the issues. Most Web
developers are not
personally opposed to
the
concept
of making the Internet
accessible to people with
disabilities. In fact, most
accessibility
errors on web sites are the
result of ignorance, rather
than malice or
apathy. A
large proportion of developers
have simply never even
thought about the
issue.
Even if they have heard of
web accessibility, they may
not understand what's
at
stake.
Their ignorance leads them to
ask questions such as,
"Why would a blind
person
want to access the
Internet?" After hearing an
explanation of the ways
in
which
blind people can access
the Internet and the
reasons why they have
difficulties
with
some sites, most of these
same developers understand
the importance of the
issue,
and most are willing to do
something about it, at least in
the abstract.
Leadership.
Understanding the issues is an
important first step, but it
does not solve
the
problem, especially in large
organizations. If the leadership of an
organization
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does
not express commitment to
web accessibility, chances are
low that the
organization's
web content will be accessible.
Oftentimes, a handful of
developers
make
their own content accessible
while the majority don't
bother to, since it is
not
expected
of them.
Policies
and Procedures. Even when leaders
express their commitment to an
idea, if
the
idea is not backed up by
policies, the idea tends to
get lost among the
day-to-day
routines.
The best approach for a
large organization is to create an
internal policy that
outlines
specific standards, procedures, and methods
for monitoring compliance
with
the
standards and procedures. For
example, an organization's policy
could be that
Web
developers will create content
that complies with the
web Content
Accessibility
Guidelines
of the W3C, that no content
is allowed to go live on the
web site until it
has been
verified to meet this standard,
and that the site will be
re-examined quarterly
for
accessibility errors. This
example won't fit every
situation or every
organization,
but it
does at least provide a simplified
theoretical model from which
to create
standards, procedures,
and monitoring methods within
organizations.
Training
and technical support
Sometimes
web developers fear that it
is more expensive and
time-consuming to
create
accessible web sites than it
is to create inaccessible ones. This fear
is largely
untrue.
On a page-by-page basis, the
extra time required by a
knowledgeable
developer
to make the content
accessible is so minimal as to be almost
negligible.
Once
developers know the concepts,
implementing them becomes second-nature,
and
does
not add significantly to the
total development
time.
However,
it does take time to become a
knowledgeable developer. A developer
can
learn
the basics of Web
accessibility in just a few days,
but, as with any
technical
skill, it
often takes months to internalize
the mindset as well as the
techniques.
Organizations
should ensure that their
developers have access to
training materials,
workshops,
books, or courses which
explain the details of
accessible web
design.
Some of
these resources are available
for free, such as the WebAIM
web site.
However,
not everyone learns best in
an online environment. Sometimes the
best
approach
is to invite an outside consultant to
provide training through
presentations,
workshops,
or one-on-one tutoring.
Ongoing
technical support can be
offered through outside
consultants, discussion
groups,
internal workshops, classes or
other methods. Some organizations
have set up
their
own internal discussion groups to
provide a forum for talking
about accessibility
issues.
If a developers forum already
exists at an organization, it may be
unnecessary
to create a
new one specifically for
accessibility if the existing
one can serve the
same
purpose.
The WebAIM forum consists of
people from all over
the world who
are
interested
in Web accessibility issues,
many of whom are highly
knowledgeable about
the
topic and willing to share
their knowledge with
others.
Conclusion
The
web offers so many new
opportunities to people with
disabilities that are
unavailable
through any other medium. It
provides a method for
accessing
information,
making purchases, communicating
with the world, and
accessing
entertainment
that does not depend on
the responsiveness of other
people. The
Internet
offers independence and
freedom. But this
independence and freedom is
only
partially
a reality. Too many web
sites are not created with
web accessibility in
mind.
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Whether
purposefully or not, they
exclude the segment of the
population that in
many
ways
stands to gain the most from
the Internet. Only by
committing to accessibility
and
providing for accountability,
training, and technical
assistance, can the web's
full
potential
for people with disabilities
become a reality.
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