1. A method, comprising: causing, with one or more processors, a computing device to display a user interface with a result of a first Boolean query applied to a data set, wherein: the user interface represents subsets of the result as concurrently displayed graphical regions; each of the graphical regions representing a respective subset of query results has a visual attribute determined based on a respective statistic of the respective subset; the user interface includes a user-selectable input by which the first Boolean query is changed, at least in part, without the user typing additional query terms; receiving, with one or more processors, a user selection entered via the user-selectable input, the user selection indicating a term to be added to the first Boolean query; based on the user selection, with one or more processors, forming a second Boolean query; applying, with one or more processors, the second Boolean query to the data set to produce a result of the second Boolean query; and causing, with one or more processors, the computing device to display the result of the second Boolean query.