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Universal Web Accessibility: Is It Possible?. Brian Kelly UK Web Focus UKOLN [email protected]. Jenny Craven, Research Associate CERLIM [email protected]. BK. Contents. Introduction Universal Access For All: The Web Architecture The People Factor Implementation Challenges: - PowerPoint PPT Presentation
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A joint CERLIM/UKOLN presentation1
Universal Web Accessibility: Is It Possible?
Jenny Craven,
Research Associate
CERLIM
Brian Kelly
UK Web Focus
UKOLN
BK
A joint CERLIM/UKOLN presentation2
Contents
• Introduction
• Universal Access For All: • The Web Architecture • The People Factor
• Implementation Challenges: • Current State Of UK HEI Web Sites • Accessibility and Usability
• Conclusions
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The Speakers
Brian Kelly:• UK Web Focus• JISC-funded advisory post • Based at UKOLN, University Of Bath
Jenny Craven:• Research Associate• Based at CERLIM, Manchester
Metropolitan University
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A joint CERLIM/UKOLN presentation4
The Web Vision
The Web was developed in order to provide universal access to digital resources, and independency from:
• Platforms • Applications • File formats
through use of open standards
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Standards
Need for standards to provide:• Platform and application independence• Avoidance of patented technologies • Flexibility and architectural integrity• Long-term access to data
Ideally look at standards first, then find applications which support the standards. However it can be difficult to achieve this ideal!
Before the Web
Access to resources typically required use of software vendor’s software – which was only available on limited no. of platforms. Often the software would be licensed.
The goal of the Web was to provide universal access to resources. Who could argue with this goal?
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The Case For W3C Standards
Why use open standards developed by the W3C? Why not leave it to the marketplace?
W3C’s open standards have been developed in an open environment, with the aim of achieving platform and application independency
Commercial companies develop proprietary formats in order to maximise their profits and dividends to shareholders
W3C’s open standards have been developed to interoperate with each other according to W3C’s design vision
Commercial companies typically develop proprietary formats in isolation, or along the lines of a company vision BK
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How Does The Web Work?The Web has three fundamental concepts:
• URLs: addresses of resources• HTTP: dialogue between client & server• HTML: format of resources
The Netsoft home page
1 User clicks on link to the address (URL)http://www.netsoft.com/hello.html
2 Browser converts link to HTTP command (METHOD):Connect to computer at www.netsoft.com
GET /hello.html3 Remote computer sends file
Welcome toNetsoft
4 Local computer displays HTML file
Web Browser
Web server
<HTML><TITLE>Welcome</TITLE>..<P>The <A HREF=“…”>Netsoft</A> home page</P>
URLs
HTTP
HTML
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HTML Is Dead!Emphasis on managing HTML resources inappropriate:
• HTML is an output format, which cannot easily be reused (e.g. WAP, e-Books, etc.)
• Need to manage HTML fragments (only partly achievable with SSIs)
• Need to manage collections of resources• Need to have single master source of data• Need to support new developments such as
personalisation• Difficult to integrate with new formats
Issues• Should we stop giving HTML training courses?• Should we stop buying HTML authoring tools?
Issues• Should we stop giving HTML training courses?• Should we stop buying HTML authoring tools?
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XML – The Key Meta FormatXML:
• Extensible Markup Language• A lightweight SGML designed for network use• A language for describing other languages• Addresses HTML's lack of evolvability• Arbitrary elements can be defined (<STUDENT-NUMBER>, <PART-NO>, etc)
• Agreement achieved quickly - XML 1.0 became W3C Recommendation in Feb 1998
• Support from industry (SGML vendors, Microsoft, etc.)
• Need for accessibility support in from start
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XML Concepts (1)
Well-formed XML resources:Make end-tags explicit: <li>...</li>Make empty elements explicit: <img ... />Quote attributes <img src="logo.gif" height="20"Use consistent upper/lower case
<p> and <P> are different
XML Namespaces:Mechanism for ensuring unique XML elements e.g. a library application containing the TITLE of the XML page, the TITLE of a book and the TITLE of :<?xml:namespace ns="http://loc.org/1998-001" prefix="i">
<p>Book: <i:TITLE>The Bible</i:TITLE></p><p>Borrower: <j:TITLE>Mr</j:TITLE> …
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XML Concepts (2)XML Schemas:
• Allow constraints to be applied on XML attributes• Express shared vocabularies and allow machines
to carry out rules made by people• Richer than DTDs• See <http://www.w3.org/XML/Schema>
XSLT:• A language for transforming XML from one XML
application to anothe, or to another format (e.g. PDF)
• Written in XML• Knows about XML (e.g. tree structures, etc.)• See <http://www.xslt.com/>
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XML Concepts (3)
XLink sophisticated hyperlinking:• Links that allow you to choose multiple destinations• Bidirectional links• Links with special behaviours:
• Expand-in-place / Replace / Create new window• Link on load / Link on user action
• Link databases• See <http://www.xml.com/pub/a/2000/09/xlink/>
XPointer/XPath:• Provides access to arbitrary portions of XML resource
• See <http://www.w3.org/TR/xptr/>
England
France
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Getting To XML With XHTML
XHTML:• HTML represented in XML• Some small changes to HTML:
Elements in lowercase <p> not <P> Attributes must be quoted <img src="logo" height="50"> Elements must be closed:
<p >... </ p >)<img src="logo" ... />
• Gain benefits from XML• Tools available (e.g. HTML-Kit from http://www.chami.com/html-kit/)
• See <http://www.webreference.com/xml/column6/>, <http://groups.yahoo.com/group/XHTML-L/> and <http://www.ariadne.ac.uk/issue27/web-focus/>
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CSS – Where You Define The AppearanceHTML/XHTML should be used to describe the basis document structure
CSS (Cascading Style Sheets):• Should be used to describe how documents
should be used to describe how the document will be displayed
• Separation of structure from appearance helps management (cf. modular programming)
• Designed with accessibility in mind
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W3C Standards - Conclusions
W3C are coordinating the development of new open standards which:
• Address the limitations of the original Web architecture
• Are designed to provide device and application independence
• Have accessibility considerations built-in from scratch
• XHTML and CSS are the ideal now
JC
Let us now move away from standards and consider the people aspect
Let us now move away from standards and consider the people aspect
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What is Accessibility?Ensuring systems and interfaces can be read by all users through:
• Access to hardware and software• Use of appropriate assistive technology
and accessibility features• Ensuring information can be interpreted
by the technology i.e. design for all
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Why Make Information Accessible?
• Resources provided online• Growth of online learning, online tutorials,
etc.• Inclusive society - widening access,
information for all• Legislation e.g. Disability Discrimination
Act, 1995; SENDA, 2001
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What Are The Benefits Of Universal Access?
It helps people with ………..• Visual impairments• Learning disabilities• Mobility impairments• Hearing impairments• Speech impairments• Seizure disorders
(source: Burgstahler: Universal design of distance learning)
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What Are The Benefits Of Universal Access?It also helps people who are ……
• Using a PC with graphics switched off• Working in a noisy environment• Using a PC with a slow connection• Using other Web-based devices e.g.
phones, PDAs, …
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Accessible Web Design• Text descriptions for all images and
sound• Contrasting colours• Plain fonts with adjustable font sizes• Properly labelled frames and tables• Alternatives for scripts, applets, plug-ins,
etc.
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Checking For Accessibility
• WAI Guidelines and Quick Tips Checklist
• Automated tools• Validation services• Web Audits and Policies• PEOPLE!!!!!
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So Why Are People Important?
• A Web site can comply with open standards.• A Web site can pass all the automated
accessibility checks.• A Web site can appear to be accessible, BUT• An accessible Web site is not necessarily usable.• The best way to test for usability is by involving
PEOPLE, i.e. the users
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Usability Issues• Appropriate alternative text for images,
links, etc.• Use of unambiguous language• Clear and consistent layout and labelling• Logical navigation of forms, search
screens, etc.• Interactive elements: online chat, quizzes,
new windows, pop-up windows, …
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Checking For Usability• Automated checkers e.g. LynxView,
Bobby, …• Ensure features can be altered e.g. font
size, colours, etc.• Try pages with graphics turned off,
different colours, etc.• Try pages using a number of Web
browsers
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Checking For Usability
• Sample size ….. Don’t panic!!!!
Ideally, try to use a sample of:• People with mixed abilities i.e.
experienced, novice, visual impairment, hearing impairment, etc.
• People using different assistive technologies
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Checking For Usability
• Observation• Transaction logging• Verbal protocol• Questionnaires and/or interviews
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Implementation Challenges
We have:• Given an overview of the Web framework, the
importance of standards, and the development of new, richer standards
• Outlined the importance of a people-oriented approach to complement the technical architecture
• Outlined basic design principles for usable and accessible Web services
This sounds great in theory, but what around real-world deployment issues:
• An accessibility & usability case study• Challenges at the institutional level
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Case Study: The NoVA ProjectNoVA: Non-visual access to the digital library:
To develop understanding of the information seeking behaviour of blind and visually impaired people in Web-based digital library resources.
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NoVA Usability Testing• Sample of 20 ‘sighted’, 20 ‘visually
impaired’ users.• Semi-structured tasks using four
electronic resources.• Map search process together with verbal
dialog.• Pre- and Post-task questions
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Examples Of Observations• Surveying page• Time taken• Types of mouse clicks and keystrokes• Problems experienced• Tackling problems• Successful interaction• Performance of assistive technologies
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Examples Of Usability QuestionsNavigation
Searching
Browsing
Results
Getting lost
Other resources
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Conclusions Derived From NoVA Usability Testing
• Usability issues• Design issues• Training issues• Software issues
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Implementation Challenges
In the real world we are faced with several implementation challenges:
• Deficiencies in specs, tools, etc.• Migration and support implications• Addressing user needs and resourcing
implications and not just technical considerations
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The Real World Web
In the real world Web we need to recognise several external factors:
• Due to the rapid development of Web specs ("the Web year") the specs themselves may be flawed, ambiguous or over-ambitious
• Software has bugs (the cockup theory)• Software vendors have their own agendas
(conspiracy theory)
Together with local factors:• Inertia / unwillingness to act as guinea pigs• Licensing costs• Support issues• …
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UK HEIs - A Case Study
In Sept 2003 a survey of accessibility of 160+ UK HEI entry points was carried out:
• Used Bobby tool (to report on problems which could be spotted using an automated tool)
• How many WAI AA entry points were found?
The survey found:• 4 entry points complied with WAI AA• One was a JavaScripted site (so isn't accessible)
The UK HEI Web management community is aware of importance of accessibility and wants to implement accessibility. What are the difficulties?
See <http://www.ariadne.ac.uk/issue33/web-watch/>See <http://www.ariadne.ac.uk/issue33/web-watch/>BK
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UK HEIs - A Case Study (2)
An example of a AA-approved site is the University of Bristol
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UK HEIs - A Case Study (3)
Typical problems found:• Missing DOCTYPES• Missing ALT attributes in IMG tags• Use relative sizing and positioning (% values)
rather than absolute (pixels)
The first two problems could be fixed with little effort on a single page
The third problem may conflict with usability criteria
Let us now:• Look at the challenges in accessible Web sites
(and not just pages)• Consider the usability issues
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WAI Implementation ChallengesMany University Web managers want to comply with WAI but have encountered implementation challenges:
• Limitations of authoring tools• Browser bugs (e.g. Netscape 4)• Apparent conflicts between usability and
accessibility• Resource implications of deploying new tools,
training, etc.• The scope of large institutional Web sites• Finding the funding
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WAI Implementation ChallengesOne Web manager commented that " I too have recently been struggling with just how rigorously the WAI guidelines should be implemented. … I certainly aspire to comply as fully as I can with the WAI guidelines but ":
• Some guidelines are too theoretical• Will have a pragmatic approach:
• Use tables for positioning• Will not associate form controls for search
boxes• Not necessarily nest headers correctly
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Accessibility Policies
You may wish to have an institutional accessibility policy
All resources on the University Web site will comply with WAI AA
All resources on the University Web site will comply with WAI AA
But:• Is this practical• All Web sites?• What about MS Word / PowerPoint documents?• How will compliance be audited?• What about difficult areas (e.g. 3D maps)?• What about people? What about usability?• How will this be funded?• Is this policy intended to be rigorously enforced, or
does it define an aspiration?
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Conclusions
Standards• Use of open standards promises to provide a rich
and platform- and application-independent framework which the HE sector needs
• However deployment of standards-based services in a real-world context is not necessarily easy
Accessibility• Technical aspects are an essential but not sufficient
condition• Ensure that user issues are addressed• You should address usability issues alongside
accessibility• There is probably a need for an accessibility
institutional policy – but thought will be needed for this
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Advice and Good Practice
• World Wide Web Consortium (W3C), Web Accessibility Initiative: <http:// www.w3.org/WAI/>
• REVIEL Project - Good Design Principles: <http://www.cerlim.ac.uk/projects/reviel/resource.htm>
• Usable IT Web site: <http://www.useit.com/>
• NoVA project final report: <http://www.cerlim.ac.uk/projects/nova.html>