A user interface for selecting an audience segment from a pool of tracked entities based on an aggregate similarity of the audience segment to an archetypical audience. The user can display a graphical representation illustrating a relationship between a composite index for the audience segment and an audience segment size and indicate the audience segment through the user interface. The user input indicating the audience segment is received by a system and the composite index and the audience segment size associated with the audience segment, are determined based at least in part on the user input. The composite index and the audience segment size associated with the audience segment are displayed.