Abstract :
We report quantitative and qualitative results of an
empirical evaluation to determine whether automated
assistance improves searching performance and when
searchers desire system intervention in the search
process. Forty participants interacted with two fully
functional information retrieval systems in a counterbalanced,
within-participant study. The systems were identical
in all respects except that one offered automated assistance
and the other did not. The study used a
client-side automated assistance application, an approximately
500,000-document Text REtrieval Conference
content collection, and six topics. Results indicate that
automated assistance can improve searching performance.
However, the improvement is less dramatic
than one might expect, with an approximately 20% performance
increase, as measured by the number of userselected
relevant documents. Concerning patterns of
interaction, we identified 1,879 occurrences of searcher–
system interactions and classified them into 9 major
categories and 27 subcategories or states. Results
indicate that there are predictable patterns of times
when searchers desire and implement searching assistance.
The most common three-state pattern is Execute
Query–View Results: With Scrolling–View Assistance.
Searchers appear receptive to automated assistance;
there is a 71% implementation rate. There does not seem
to be a correlation between the use of assistance and
previous searching performance. We discuss the implications
for the design of information retrieval systems
and future research directions.