This thesis reports results of a research study into the usefulness of a user-centred
approach for designing information retrieval interfaces. The main objective of the
research was to examine the usability of an existing Web-based IR system in order
to design a user-centred prototype Web interface. This research used the Web of
Science available at http: //wos. mimas. ac. uk.
A series of usability experiments was carried out with the Web of Science. The first
experiment was carried out using both novice and experienced users to see their
performance and satisfaction with the interface. A set of search tasks was obtained
from a user survey and was used in the study. The results showed that there were
no significant differences in the time taken to complete the tasks, and the number
of different search terms used between the two search groups. Novice users were
significantly more satisfied with the interface than the experienced group. However,
the experienced group was significantly more successful, and made fewer errors
than the novice users.
The second experiment was conducted on novices' learning and retention with
the Web of Science using the same equipment, tasks and environment. The results
of the original learning phase of the experiment showed that novices could readily
pick up interface functionality when a brief training was provided. However,
their retention of search skills weakened over time. Their subjective satisfaction
with the interface also diminished from learning to retention. These findings
suggested that the fundamental difficulties of searching IR systems still remain with
the Web-based version.
A heuristic evaluation was carried out to find out the usability problems in the
Web of Science interface. Three human factors experts evaluate the interface. The
heuristic evaluation was very helpful in identifying some interface design issues for
Web IR systems. The most fundamental of these was increasing the match between
system and the real world.
The results of both the usability testing and the heuristic evaluations served as a
baseline for designing a prototype Web interface. The prototype was designed
based on a conceptual model of users' information seeking. Various usability
evaluation methods were used to test the usability of the prototype system. After
each round of testing, the interface was modified in accordance with the test findings.
A summative evaluation of the prototype interface showed that both novice and
experienced users improved their search performance. Comparative analysis with
the earlier usability studies also showed significant improvements in performance
and satisfaction with the prototype. These results show that user-centred methods
can yield better interface design for IR systems.
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.