1. A computer-readable storage medium having instructions stored thereon for processing data information, such that the instructions, when carried out by a processing device, enable a processing device to perform the operations comprising: receiving an ordered collection of text-based terms; analyzing groupings of consecutive text-based terms in the ordered collection to identify occurrences of different combinations of consecutive text-based terms in the ordered collection; and maintaining frequency information representing the occurrences of the different combinations of consecutive text-based terms in the collection.
3. The computer-readable storage medium of claim 1 wherein the operations further comprise, based on the analyzing, creating a tree in which a first term in a given grouping of the groupings is defined as a parent node in the tree and a second term in the given grouping is defined as a child node of the parent node in the tree, both the first term and the second term in the given grouping being consecutive text-based terms present in the order collection.