Combined search paradigms (Facets and Timelines) comprise both the conceptual and the keyword search paradigms. They provide advanced tools for retrieving information about entities, points in time or time intervals, and terms that appear together in the same context in the document set. In other words, Combined search paradigms help you find unknown entities by defining the environment in which they appear (relations with other entities, dates, or terms).
This co-occurrence-based faceted search capability is a method of aggregating a popularity rank for entities. How frequently an entity occurs in a context can signify its association with this context. From the frequency of occurrence you can determine if such relation exists and how strong it is. This way you can track some statistics for the relations between entities and documents.
If you have large amounts of data to work with, you can also analyze some very interesting relations between the entities in the domain that shape trends and dependencies. The scalability of these paradigms allows you to search quickly and effectively for these correlations through extensive sets of documents.