Exploring the Use of Query Auto Completion: Search Behavior and Query Entry Profiles.

Query auto completion (QAC) is nearly ubiquitous in modern search systems, however, there are few published studies on how searchers use QAC query suggestions. This study describes the use of QAC by 29 searchers working on eight assigned search topics in a lab setting. We found that our subjects had differing propensities to use QAC, with some searchers rarely using it, while others used QACs for about half their queries. This study extends prior work by examining the use of QAC in the context of whole search sessions across multiple topics, and by comparing search behavior and visual attention for queries that used QAC and those that did not. The study concludes with an exploration of differences in QAC usage and query behavior among searchers, which reveals six possible query entry profiles.