User Exploration of Slider Facets in Interactive People Search System

People search is an important search task where the goal is to find people instead of documents. Providing search facets in a people search system can help users better describe their search intents. Some systems provide checkboxes for the discrete values of each facet to assist users filtering search results. Some other systems in recent studies provide sliders to represent the continuous values of facets. Slider facets enable an interactive search system to handle the facets without discrete values. Yet, the ways of how users interact with slider facets are rarely studied, particularly for people search tasks. Based on a user study with 24 participants using an interactive people search interface with three slider facets, we find that users indeed utilize the slider facets consistently in their search processes to fine-tune the search results ranking. We also find that although tuning the slider facets values can bring performance boost but users are lack of abilities to locate the optimal facet-values, which indicates the necessity of providing automatic facet-value suggestion.