1. A computer implemented method of putting items into categories, the method comprising: (a) dividing a plurality of items of a data structure into a plurality of groups, wherein each group contains one or more items divided into that group; (b) performing a first ranking of one or more items within each group of the plurality of groups, such that each item has a set of befores and a set of afters, wherein the set of befores is a set of items ranked higher than an item, and the set of afters is a set of items ranked lower than an item; (c) selecting, according to a what-if scoring methodology, at least one best group from the plurality of groups for a subsequent ranking, wherein the what-if scoring methodology includes determining which items from the at least one best group will yield a maximum amount of new information upon performing the subsequent ranking; (d) performing, via processor execution, the subsequent ranking of the one or more items within the at least one best group; (e) cascading the befores and afters of the one or more items of the at least one best group according to the subsequent ranking, wherein each item of the one or more items inherits a set of afters from each other item ranked after that item and a set of befores from each other item ranked before that item; (f) determining which of the plurality of items are categorized, wherein an item is determined to be categorized when that item is in exactly one category; (g) removing each categorized item of the plurality of items from the data structure, wherein each removed categorized item is removed from further consideration; (h) in response to finding one or more invalid rankings of a subset of items: discarding the one or more invalid rankings of the subset of items of the plurality of items, wherein the one or more invalid rankings are associated with a particular source from a plurality of sources; and re-ranking the subset of items; and (i) repeating steps (c) through (g) until all of the plurality of items have been categorized.