accessibility studies and sizes
This page looks at writing about accessibility problems,
standards and issues.
It covers -
Jakob Nielsen's Designing Web Usability: The Practice
of Simplicity (Indianapolis: New Riders 1999) and
newsletter are strongly recommended. He has drawn
together many of the issues in an article
on Disabled Accessibility: The Pragmatic Approach.
Nielsen's Usability Engineering (New York: Academic
Press 1993) is somewhat more demanding but draws on extensive
empirical studies in discussing principles and practice.
Ben Schneiderman's Designing The User Interface: Strategies
for Effective Human-Computer Interaction (Reading:
Addison-Wesley 1998) is excellent. It is supported by
a companion site.
Yale University's masterful Web Style Guide: Basic
Design Principles for Creating Web Sites (New Haven:
Yale Uni Press 1999) by Patrick Lynch
& Sarah Horton is also recommended; there is an online
version that is both informative and a minor work of art.
It complements Nielsen and has a practical approach to
the use of Cascading Style Sheets (CSS). A broader perspective
is provided by the excellent Columbia Guide To Digital
Publishing (New York: Columbia Uni Press 2003) edited
by William Kasdorf.
The Design guide elsewhere
on this site points to other works, such as Cooper's classic
About Face: The Essentials of User Interface Design,
Raskin's The Humane Interface: New Directions for Designing
Interactive Systems and Advances in Universal
Web Design & Evaluation: Research, Trends & Opportunities
(Hershey: IDEA Group 2007) edited by Sri Kurniawan &
Web Site Usability: A Designer's Guide by Jared
Spool, T DeAngelo & others (New York: Academic Press
1998) and Web Accessibility for People With Disabilities
(Lawrence: CMP 2000) by Michael Paciello are recommended.
Other sources worthy of investigation are the Usable
and the resources on the Usability Professionals' Association
site. The Bad Designs site
offers offline points of reference.
US disability engineering expert Jon Gunderson has explored
World Wide Web Browser Access Recommendations
as part of his work on MOSAIC and has a paper
on World Wide Web Accessibility to People with Disabilitities:
A Usability Perspective.
Donald Case's broader Looking for Information: A Survey
of Research on Information Seeking, Needs, and Behavior
(New York: Academic Press 2002) is commended. Other resources
about information seeking are highlighted here
and here. The 2006
US National Council on Disability paper
Over the Horizon: Potential Impact of Emerging Trends
in Information and Communication Technology on Disability
Policy and Practice offers perspectives on potential
future accessibility challenges.
economics, security and business cases
For introductions to the 'case for usability' see in particular
The Politics of Usability: A Practical Guide to Designing
Usable Systems in Industry (London: Springer-Verlag
1998) edited by Lesley Trenner & Joanna Bawa and Cost-Justifying
Usability (New York: Academic 1994) edited by Randolph
Bias & Deborah Mayhew. Security and Usability
(Sebastopol: O'Reilly 2005) edited by Lorrie Cranor
& Simson Garfinkel is of particular value.
We've highlighted works and issues regarding the politics
of accessibility on the final page of this guide.
Perspectives on systematising accessible design are provided
in Institutionalization of Usability: A Step-by-Step
Guide (Reading: Addison-Wesley 2004) by Eric Schaffer.
Statistics about the devices
with which people access online content are problematical.
The July 2001 WebSideStory survey
claimed that the most common screen resolution was 800
x 600 pixels. Subsequent reports from WebSideStory and
other sources suggest that there was a slow change, with
800 x 600 being surpassed as the dominant screen resolution
worldwide in April 2003.
WebSideStory claimed in August 2003 that 58% of web users
used a screen resolution of 1024 x 768 or higher, up from
34% in January 2000 and 20% in January 1999. The number
viewing with 640 x 480 is claimed to have fallen to 5.71%
from 17.83%; the 1152 x 864 and 1280 x 1024 sizes have
shown small gains since 1999 and now account for around
5% of the market.
There is however significant national/regional variation,
which may reflect data sources.
Globally the figures as of mid 2002 were claimed to be
of the online population uses a 1152 x 864 monitor
2.9% uses 1280 x 1024
32.7% uses 1024 x 768
52.5% uses 800 x 600
5.7% uses 640 x 480
people are continuing to rely on desktop monitors and
laptops rather than PDAs or mobile phones.
Accessibility challenges are not restricted to physical
disadvantage (eg poor sight or motor impairment). They
also encompass geographical location and economic disadvantage,
eg trying to access online content via a slow connection
in remote Australia.
Statistics about the online population feature in the
Metrics & Statistics
guide, supported by a more detailed examination of Australian
and international Digital
Divides. Background about Australia's telecommunications
infrastructure is here.