Usability...
Ubiquity Does Not Guarantee Usability.
"Click here". You may see these words on many web sites, but that does not
make
it any easier to figure out what they mean. Each time this blue, underlined
phrase attracts your attention, you have to read the words around it to know
where this link will take you. Ubiquity does not guarantee usability. Familiar
words and common interface elements contribute to the usability of a web site,
but many other aspects are involved.
The goal of usability evaluation is to determine what can be done to make an
interface efficient, satisfying, and easy to use, to learn, and to remember.
Usability evaluation involves selecting some of the various methods designed
to glean this information and applying them iteratively, from the early stages
of a web site's development through its active use. These methods may include
interviews, focus groups, card-sorting tests, link-naming tests,
scenario-based tests, cognitive walkthroughs, and heuristic evaluations. At
the Digital Knowledge Center, many of our methods entail inviting the
library's "target users" to discuss their needs and goals in using the
library's web resources and to participate in sessions in which library staff
observe their use of a library web site. We seek participants that represent a
cross-section of the university community: students, faculty, and staff in
different fields of study and at different levels of familiarity with the
Johns Hopkins University Libraries.
In addition to providing usability evaluation for various library web
projects, the Digital Knowledge Center conducts research on digital library
usability. We seek to find the best methods for evaluating the usability of
digital library resources. Our
Usability
Research Agenda discusses the issues and
opportunities that arise in this quest.
Types of Tests
- Focus group
In a focus group, 8-10 participants talk about how they use the library's web
site and what they want it to be able to do in the future. A library staff
person facilitates the conversation and shares a summary with the library web
site design team.
- Scenario-based test
In a scenario-based test, two library staff members observe a participant
using a web site to complete specified tasks. Seeking to learn what they can
do to make the site easier to use, they note how the participant interacts
with the site.
- Card-sorting test
In a card-sorting test, each card represents one page in the web site being
evaluated. Each participant sorts a stack of cards into groups and assigns
labels to the groups. The results help library staff decide how to group the
links that lead to those pages.
- Heuristic evaluation
In a heuristic evaluation, a usability specialist inspects a web site to
determine if it meets general guidelines for usability and accessibility, such
as consistency in navigation, clarity in language, and flexibility in the pace
of interaction.
Projects
The Digital Knowledge Center has worked with other library departments and
groups outside the library to evaluate the usability of a variety of web
sites. We have held scenario-based tests for the Project Muse search engine,
the library homepage, and the library catalog interface. We have worked with
Special Collections to conduct an online survey of the Roman de la Rose site,
and we are working with them on the digital sheet music harvester usability
project.
Resources
For more information about usability, check out the following resources:
Last updated August 5, 2003
