|
Web Site Usability: A Designer's Guide,
Spool, J.M., Scanlon, T., Schroeder, W., Snyder, C. and DeAngelo, T. (1997),
North Andover, MA: User Interface Engineering.
|
Good, research-based information is very sparse concerning the design
and development of effective Web sites. Few studies have tried to answer
basic Web usability questions. One of these was published by Spool and
his colleagues (1997). They tried to identify the design decisions that
help, and those that hinder, users' attempts to find information in a
large Web site. Some of their conclusions are:
- Sites can be designed to facilitate either searching or browsing,
but not both.
- Most sites do not help users compare information.
- Users did not seem to become familiar with the layout of sites (or
develop useful mental models).
- Well-designed frames did not hinder users. But they didn’t help
users either.
- Users preferred to scroll to the bottom of pages to press final buttons.
- In-site search engines were not generally used; and when they were
used, they didn’t improve
- search performance.
- Text links were more important in these search tasks than graphic
links.
- The most difficult-to-use sites were more "graphically intense."
- The best-liked sites were not the same as the most easily searched
sites.
Web designers make daily design decisions with little guidance from research-based
literature. Good studies, like this one, will help usability specialists
make better initial decisions.
|
|
Designing Effective Multimedia Presentations,
Faraday, P. and Sutcliffe, A. (1997), Proceedings of CHI '97, pgs. 272-278.
|
You have a choice: listen to the speech and read the text, or view the
multimedia version. Will the multimedia presentation improve recall more
than speech and text alone?
The multimedia research literature has few helpful published studies
on how design affects learning.
Most guidelines come from highly subjective opinions of multimedia developers.
Faraday and Stucliffe (1997) conducted four studies and showed the value
of controlling shifts of attention with multimedia. In the first study,
they tracked eye-movement patterns during the multimedia presentation.
From this, the authors identified guidelines for improvement, including:
- Provide more time for reading captions.
- Avoid animation that distracts attention from other, more important
information on the screen.
- "Reveal" information systematically to control attention
(use a "wipe" left-to-right or top-down).
- Limit reveals to one item at a time and use sequential reveals for
related elements.
- Avoid animation or reveal motion during the moment of speech when
a label is being mentioned.
The second study determined that multimedia design influenced recall
more than any prior
domain knowledge. This study also resulted in additional design guidelines:
- Speech should reinforce the image including captions and labels.
- To imply a clear cause and effect relationship, animation must show
more than just the initiation of an action. It must show the result
as well.
In the third study, Faraday and Sutcliffe revised the multimedia presentation
based on their findings and found that participants recalled more information.
The new design guidelines based on eye-tracking aided comprehension and
recall.
In the fourth study, subjects read and listened to the text-only portion
of the revised multimedia presentation from study three. The poor recall
of subjects in study four compared to study three indicated that the images
and animation provided important additional reinforcement of the knowledge.
|
