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Noushin Aslam
Title:
Usability and Accessibility of the websites
Noushin Aslam
Noushin Aslam
Acknowledgements
Many Thanks to J. Elliot who has provided enormous help and guiance in order to
gain success in research project.
ABSTRACT
The emergence of the World Wide Web has allowed individuals with suitable computer
and telecommunications equipment to interact as never before. This cyberspace junction
of data, computers, networks, and multimedia presents exciting challenges to interface
designers.
It has become an essential part of our lives such as point of sale in a supermarket, online
banking and e-commerce or a word processor in an office all have become a primary and
essential part of life. Most of us at sometime or other have experienced difficulty and
frustration when trying to use the technology. In many cases much time and energy has
been used and lives have been lost in the struggle.
“However, this “new technology frontier” has also created
enormous roadblocks and barriers for people with
disabilities.
This report discusses specific issues, suggests potential solutions and seeks assistance
required to design a Web interface, which is easily accessible by everyone including
people with disabilities. HCI guidelines and principles will be discussed to develop and
enhance web usability.
Critical evaluation HCI guidelines will be carried out to enquire whether they provide
complete success in terms of usability standards.
Noushin Aslam
Table of Contents
Table of Contents ........................................................................................................... 3
1. Introduction ................................................................................................................ 4
1.2 Aim ...................................................................................................................... 5
1.3 Objectives ............................................................................................................ 5
1.3.1. Importance of usability. ................................................................................. 5
2. Literature Review....................................................................................................... 6
2.1 Web _ Accessibility ............................................................................................. 9
3. Conclusion ............................................................................................................... 17
4. Recommendations .................................................................................................... 17
5. Bibliography ............................................................................................................ 18
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1. Introduction
A computer system which allows users to carry out particular tasks
Safely
Effectively
Efficiently and
Enjoyable!
These aspects are known as usability.
Usability is the most successful factor in any web page design as it measures is about how
easy a website to navigate and understand. Websites are a crucial source of information
in
particular, the World Wide Web enables global distribution of products and services
through websites.
Accessibility is about catering people with disabilities, HCI studies have ‘evoked many
difficult problems and elegant solutions’, yet unfortunately there are hundreds of
examples of websites which have failed to provide good usability and disadvantaged
many users to access important information.
Therefore government as well as hci studies have established guidelines and accessibility
laws (Disability Discrimination Act 1995 - Word) in order to ensure the accessibility of
websites for different users. Hence, website developers need to think what should be
done.
"In the past, designers were constrained by what could be done; now designers
can think about what should be done." (Eberts, 1994).
The following are aims and objectives of the this report
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1.2 Aim
The aim of the report is to investigate usability and accessibility issues of websites.
Highlight importance of web usability, most importantly to provide possible solutions
and outline ways in which to specify and design more usable interface.
1.3 Objectives
To identify major issues with usability and accessibility of websites.
Investigate web accessibility for people with special needs.
Explore HCI guidelines for web interfaces and Conduct critical analysis of HCI
guidelines
Highlight accessibility law for web interfaces. .
Suggest potential Solutions for problems encountered.
1.3.1. Importance of usability. Number of internet users is increasing day by day which has increased importance of
web usability. A system which is easy to use and access can improve everyday work life as
computers are almost part of every job.
(Jenny preece) highlights a Well designed computer systems with good usability can
Improve the performance of the work
Improve the quality of life
Make the world a safer and enjoyable place to live in.
Faults with the usability of the system can sometime cause disasters and lead to
unpredictable incidents.
“In the aftermath of the September 11, 2001 terrorist attacks, some members of
the US Congress blamed the inadequacies of user interfaces for the failure to
detect the terrorists” (Shneiderman and Plaisant 2005)
There are many Reasons for ensuring website accessibility such as
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As noted by W3C (2003a):
“the Web is becoming a key resource for:
• news, information, commerce, entertainment,
• classroom education, distance learning,
• job searching, workplace interaction,
• Community participation, government services.
It is displacing traditional sources of information and interaction –
• schools, libraries, print materials, discourse of the workplace;
• some of the traditional resources were accessible; some not”.
Therefore it has become crucial for website designers and developers to consider
different users and priorities usability and accessibility of computer systems
especially for websites.
There are more than 50 million disabled people in Europe (TAP 1997, cf. Dix et al
2004, BCS 2000). Most websites around the world are failing a basic accessability
standard which means all these people are suffering to advantage from the benefits
of the World Wide Web. The designers need to focus on users rather than the actual
system.
“Users share common capabilities but are individuals with differences, which
should not be ignored” (Dix et al 2004 p 11)
2. Literature Review
Due to the rapid growth of World Wide Web in the recent past, 'usability' has emerged as
problems of concern to the researchers.
“recognise lack of usability when we encounter it, even though we may not label
it as such.” [Dix, et al 1998].
Usability ensures that regardless of how, when, or where your users enter your website,
they will be able to use it “efficiently, effectively, and satisfactorily.”
Faulkner (2000) explains usability in simple and easy terms, “How easy it is to learn or
use a system”
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Human computer interaction is the study and the practice of usability. (it is about
understanding and creating software and systems which people will want to use and will
find effective when used).
It is the resource of communication between the user and the computer.
Thus, the objective of human computer interface design is to increase the usability of the
system, in order to help users reach acceptable performance levels.
The following section will highlight the major usability problems with current websites.
Through the research it has been found that the main reason for many websites to fail
usability tests is problems like pitiable navigation systems and lack of user’s
understandings of the system.
Fourth international conference on software engineering research, management and
applications, proceedings: revealed. 2006 “Large web systems are being made so complex
that often the users have to make excessive amount of 'navigational efforts' to complete
their tasks. We identify certain -aspects which aggravate the 'navigational burden' of a
user. Vital amongst them are, complex navigational structure of web, unfamiliarity of
users with the website, and disagreement between the research community and
practitioners.”
The user interface design process focuses on understanding users and their individual
differences. Therefore, designers really need to focus on different individuals’ needs as
most of us suffer from usability problems such as finding your way around and waiting a
lot of time understanding the structure of the website. The author believes it is very
frustrating for the user to not be able to accomplish a particular task or find important
information in reasonable amount of time. Many people rely on internet for important
information e.g. it has been reported that 80% of adult Internet users have accessed it for
general health information. Sillence .E (2005)
Survey results – “on average 5.1 hours per week wasted by people trying to use their
machines…users waste more time in front of computers than on highways”
(Shneiderman 2002 p 25)
Nielsen (2000) argues for the importance of web usability:
• Many web sites – estimated 100 million
– Hence users have much choice, and will leave a site very rapidly if they
cannot work out how to use it
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Therefore designer must focus on user needs.
Lack of consistency is another major reason which creates barriers for different users
to learn or use a system. The author believes consistency and simplicity is the key to
develop a successful user interface. However, it has been argued that consistency can be
regarded as a usability category in its own right, with many of the other usability
principles appearing in support of consistency [Dix, et al 1998].
Enormous number of websites shows lack of consistency such as major problems
encountered with evaluated website (Leeds met university) are navigation and
consistency.
Common interface design problems that affect individuals when accessing websites are
noted by Vassallo (2003) and include:
• small fonts;
• poor contrast backgrounds (either too low or too high);
• large blocks of text;
• cluttered pages;
• animated images or blinking/moving text;
• automated page or form redirects;
• fully justified text (resulting in uneven spacing between words); and
Wordy and confusing use of English
This means most of the websites are produced by designers which are not fully aware of
HCI evaluation techniques and process of user interface design and are unable to
differentiate between individuals’ needs and expectations from the system. The author
suggests that these issues could have been addresses by carrying out early evaluation with
users to ensure that the system is designed to meet their needs.
“Usability is often the most neglected aspect of web sites, yet in many respects it is the
most
Important” (Nielsen, 2001).
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2.1 Web _ Accessibility
Since the mid 1990s, hundreds of articles and design resources have been produced to
increase accessibility. Still Millions of people with disabilities are surfing the Internet
every day and large number of websites are failing to cater people with disabilities
Ninety seven percent of websites did not provide even minimum levels of
accessibility standards for people with disability, a new survey has found. Can be
found here http://news.bbc.co.uk/1/hi/technology/6210068.stm
There are several reasons why accessibility is a key issue such as a large proportion of
our population require special needs. The above information also concludes that many
designers an organisation have not considered DDA 1995 so designer must consider
usability and accessibility of website to make it legally right according to DDA 1995.
Author believes the designers are failing to understand the needs of disable users even
there is a large number of audiences with special needs;
9% males are colour blind in Uk.
B-t estimate 10% of people is disable
11.5 million People in Europe with partial sight
1.1 million Users are blind in Europe (TAP 1997)
HCI literature enforces cognitive, physical and social issues related to people with special
needs should be considered to increase website accessibility for as many people as
possible.
The cognitive issues e.g. does user know the system or physical issues such as if user is
visually impaired or hearing problems must be considered as large number of the
individuals have hearing impairments, Physical impairments and visual impairments.
“As humans … we have certain limitations, both cognitive and physical. Products
designed to support humans should take these limitations into account.” (Preece
et al 2002,).
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Therefore every website must provide accessibility to as many individuals as possible to
make sure that people with disabilities are not left behind.
"The power of the Web is in its universality. Access by everyone regardless of disability is an essential
aspect." - Tim Berners-Lee, director and inventor of the World Wide Web (W3C, 2003a)
The author believes there is an extreme need to provoke understanding of HCI
evaluation methodologies and guielines. The W3 standards have also developed website
accessibility guidelines for people to improve HCI to cater people with special needs.
Many website lack websites lacks features such as resizable fonts, images with proper text
descriptions, and easy navigation, these people will not be able to access your
information. The survey results (reported by BBc 25 December 2006) below illustrate the
major problems which make website inaccessible for a large proportion of our
population.
93% failed to provide adequate text descriptions for graphics
73% relied on JavaScript for important functionality
78% used colours with poor contrast, causing issues for those with colour
blindness
98% did not follow industry web standards for the programming code
97% did not allow people to alter or resize pages
89% offered poor page navigation
87% used pop-ups causing problems for those using screen magnification
software
Social reasons – organisations should feel grateful to be socially responsible and work
towards removing discrimination and promoting human rights (HREOC, 2002). This
will help making their website accessible every individuals, including those with
disabilities.
Economic / business reasons – it does not make economic sense for organisations to
exclude 10% of potential customers who may have a disability (HREOC, 2002). An
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inaccessible site may result in users with disabilities leaving for competitor sites or
switching to more expensive options, such as call centers and walk-in branches.
“While a program’s design and technology affects its overall capability
and performance, as far as the user is concerned, the user interface is
the program. If the user interface isn’t good, the program isn’t good”
(McKay 1999 p xvi)
What needs to be considered by designers?
The author believes greater effort is needed to provoke awareness of techniques and
guidelines developed by HCI theory to improve accessibility and usability of websites
.Most poorly designed website suffers from a lack of awareness and focus on users so
designers need to consider
who they are, what they want, how they work, and how they really use computers. To
improve Human computer Interface designers need, designers need to do research,
explore literature, and evaluate and test website designs with there targeted audience.
A focus on users—developing with users
and not for them—has become central to quality software
and Web design today. Figure 1 (Mandel, 1997)
Users should be involved in all phases of the
Design and development process.
Design iteratively with many cycles of ‘design’ – evaluate with users – ‘redesign’
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Paper Prototypes-
HCI suggests using Paper Prototypes; -the author believes these should be use at early
stage of evaluation such as producing designs on paper then directly evaluate and discuss
it with. Paper based prototypes such as storyboards are quick cheap and easy to make
and amend.
A common response from programmers after receiving an accessibility evaluation is that
it would have been much easier to incorporate the requested changes at the beginning of
the site development lifecycle
Robert Bailey 2005 argues Most existing sets of web design guidelines tend to be loosely
linked to research so reason, designers tend to struggle in deciding how seriously they
should consider each of the guidelines. Therefore designers need to apply suitable
guidelines very intelligently to improve accessibility.
Bailey [1996] suggests that it is the designers, who should be held responsible for
reduced human performance,
particularly if ‘poor design decisions resulted from ignorance of human performance
technology’. Therefore, to
improve performance, designers must know what factors affect it [Mayhew 1992].
Consistency
Enforce and maintain consistency thought designs as this will increase learnability of the
system and help user to understand structure of website easily.
It has been stated that consistency is one of the basic principles of usability [Dix, et al
1998] that can be used to improve human performance.
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Culture
It is suggested that in order to design an interface that is fully consistent to the user, the
designer needs to accommodate
cultural dimensions as well as the user profile variables into the design of the user
interface. This is supported by many
authors, including Marcus [2001],
Legislation
The Disability Discrimination Act 1995 - Word (the DDA), was introduced with the
intention of comprehensively tackling the discrimination which many disabled people
face. The part of the DDA that states websites must be made accessible came into force
on 1 October 1999 and the Code of Practice for this section of the Act was published on
27 May 2002.
This was to make sure that all users have equal right to avantage facilitation of World
Wide Web including people disabilities. However 90% of the websites have failed
accessibility standards and
Guidelines for web development
HCI suggests one approach to addressing the complexity is to follow a set of guidelines
or principles. Sutcliff claims (1995) guidelines have met limited success. Author believes
this could be another reason for many websites to fail usability and accessibility which
have been envelope incorporation with different guielines..
Guidelines
Some terminological disagreement in the literature, eg we get “principles”, “guidelines”,
“rules”.
“principle” = high level advice that can be applied widely (Preece 1994)
eg know the user population reduce cognitive load
engineer for errors
“Guideline” = lower level, more specific, needs no interpretation, eg “make the title
upper case 14 point Times New Roman”
The following are critical review of guidelines developed by different HCI experts.
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Shneiderman’s “eight golden rules” of interface design (Shneiderman and
Plaisant (2005) p 74):
1 strive for consistency
2 enable frequent users to take shortcuts
3 offer informative feedback
4 design dialogues to yield closure
5 offer simple error handling
6 permit easy reversal of actions
7 support internal locus of control
8 reduce short-term memory load
Critical Review
In the light of Hci theory and literature review of usability and accessibility websites it
appears that shniederman has not suggested anything in particular for people with special
needs.
Mandel’s (2005) three “golden rules of interface design”:
1 place users in control
2 example sub-principle - “allow users to directly manipulate interface objects”
3 reduce users’ memory load
4 example sub-principle - provide visual cues
5 make the interface consistent
6 example sub-principle - keep interaction results the same
Critical Review
The mandel suggests “Allow user to directly manipulte the interface objects”, it is
impossible to put user in control as every user has different needs.
Sutcliffe’s (1995) seven principles derived from HIP research:
1 Consistency
Be consistent across tasks. Screens etc.
Reduces learning load and increases recognition
2 Compatibility
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Aim for good fit between user’s expectations and reality of and interface design
Have new designs compatible with user’s previous experience
3 Predictability
Interface should suggest to the user what actions are possible
Hence need appropriate messages, prompts, icons....
Aids users in their planning
4 Adaptability
Interface should adapt to its individual user
5 Economy and error prevention
Aim for minimum number of steps to achieve a task
Consider dialogue short cuts
Help user avoid disastrous errors (“Are you sure? Y/N”)
6 User control
User should be and feel in control - relates to predictability
“Undo” is important aspect
7 Structure
8 Structure interfaces to reduce complexity.
Critical Review
The sutcliffe’s rule one “Be consistent across tasks”.
contraicts with rule “Interface should adapt to its individual user”
as it is not possible to make a system which is comletely consistent and then allow
adpatbility. E.gif a user makes changes to the system it will not be consistent through
out.
Noushin’s Theory
Such design is an important aspect of “universal design” – defined by Dix et al (2004, p.
366) as “the process of designing products so that they can be used by as many people as
possible in as many situations as possible”.
Noushin’s theory has been developed in corporation with shniederman, Mandal and
universal guidelines in order to increase usability and accesability for as many people as
possible.
Universal design involves these areas of human diversity: people with disabilities,
older people, children, cultural differences.
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Seven general principles of universal design have been proposed:
1 Equitable use – no user is excluded
2 Flexibility in use - design accommodates a wide range of individual preferences and
abilities
3 Simple and Intuitive Use - use of the design is easy to understand, regardless of the
user's experience, knowledge, language skills, or current concentration level.
4 Perceptible Information - the design communicates necessary information effectively to
the user, regardless of ambient conditions or the user's sensory abilities.
5 Tolerance for Error - the design minimizes hazards and the adverse consequences of
accidental or unintended actions.
6 Low Physical Effort - the design can be used efficiently and comfortably and with a
minimum of fatigue.
7 Size and Space for Approach and Use - appropriate size and space is provided for
approach, reach, manipulation, and use regardless of user's body size, posture, or
mobility.
8 Present only relevant information, in a simple manner
9 strive for consistency
10 enable frequent users to take shortcuts
11 offer informative feedback
12 design dialogues to yield closure
13 offer simple error handling
14 permit easy reversal of actions
15 support internal locus of control
16 reduce short-term memory load
17 Compatibility
Aim for good fit between user’s expectations and reality of and interface design
Have new designs compatible with user’s previous experience.
18 Structure interfaces to reduce complexity.
19 Maintain simplicity to reduce complexity (Google is the successful example of a
simple interface.
These guidelines will allow designer to increase accessibility and solve most problems.
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3. Conclusion
It has been found that a greater effort is required to provoke awareness of HCI and
Guielines. The designers need to apply right guidelines intelligently and keep main focus
on users. There is a need to provoke more awareness of needs of people with disabilities
as they are large proportion of our population and most of the websites do not cater for
people with special needs. The Government should ensure stricter enforcement on
accessibility law such as DDA, 1995 and clamp down on every organisation providing
services through the internet who do not abide by this law. Through research findings
and HCI literature a new set of guidelines have been proposed in order to help website
designers to create website which are easily usable and accessible by everyone including
people with special needs.
4. Recommendations
In the light of research a new Noushin’s Theory has been developed to help designer
including universal guidelines to make sure people from all different background cultures
and special needs are not excluded. The author recommends to critically reviewing HCI
guidelines for a specific system within corporation with user requirements.
o Carryout Early stage user evaluation, focusing on the users and the users’ needs.
o Involve users in all stages of design
o Make every website legal by DDA 1995
To expand specific disability guidelines use W3 schools accessibility guidelines
http://www.w3.org/TR/1999/WAI-WEBCONTENT-19990505/
Noushin Aslam
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