A Comparative Study of Query-biased and Non-redundant Snippets for Structured Search on Mobile Devices

To investigate what kind of snippets are better suited for structured search on mobile devices, we built an experimental mobile search application and conducted a task-oriented interactive user study with 39 participants. Four different versions of the search engine result page (SERP) were compared by varying the snippet type (query-biased vs. non-redundant) and the snippet length (two vs. four lines per result). We adopted a within-subjects experiment design and made each participant do four realistic search tasks using different versions of the application. During the study sessions, we collected search logs, “think-aloud” comments, and post-task surveys. Each session was finalized with an interview. We found that with non-redundant snippets participants were able to complete the tasks faster and find more relevant results. Participants preferred non-redundant snippets more and wanted to see more information about each result on the SERP for any snippet type. At the same time, participants felt that the version with query-biased snippets was easier to use. We also report on relevant query formulation, result examination, and result selection strategies employed by participants. We conclude with a list of design implications and a discussion on what these findings mean for the future of structured search, especially on mobile devices.