System and method for evaluating an information aggregate by analyzing categories into which each document of the aggregate is placed. A metrics database stores for each document indicia including associated categories. A query engine is responsive to a user request and the metrics database for aggregating documents having same, unique attributes in an information aggregate and identifying categories associated with documents comprising the information aggregate; and a visualization engine visualizes the category or set of categories, such as by list or distribution frequency, and changes in time over conceptual or physical space.