Exploring the Effect of Task Difficulty and Domain Knowledge on Dwell times

This study explores the effect of task difficulty on users’ search behaviors, i.e. dwell time on content pages and search result pages, by users with high and low domain knowledge. A user experiment was conducted, with 40 participants working on 5 search tasks. Participants were divided into two domain knowledge levels according to their MeSH term ratings. Among the five search tasks, three were Difficult tasks and the other two were Easy tasks. Our results demonstrated that there was interaction effect of task difficulty and domain knowledge on the dwell time on content pages. We also found that task difficulty and domain knowledge have main effect on the dwell time on search result pages. In particular, the dwell time on search result pages was much higher in Difficult tasks or by users with low domain knowledge. The results indicated that the dwell time on search result pages was better indicator of task difficulty than dwell time on content pages. Our results have implications for personalization information retrieval.