17. A non-transitory computer readable storage medium including instructions that, when executed by a processor, cause the processor to perform operations comprising: determining, by the processor, counts of documents similar to a reference document for a plurality of similarity ratings, each similarity rating being based on a number of co-occurring terms between the reference document and corresponding similar documents; presenting in a graphical user interface (GUI) the reference document and a GUI element pertaining to the documents similar to the reference document; and upon a selection of the GUI element, presenting in the GUI a second GUI element comprising similarity ratings associated with the reference document; and in response to selecting one of the similarity ratings, presenting in the second GUI element a visual representation of the counts of similar documents that indicate a number of documents that are retrievable based on the selected similarity rating, wherein the visual representation is provided prior to retrieving one of the similar documents.
17. A non-transitory computer readable storage medium including instructions that, when executed by a processor, cause the processor to perform operations comprising: determining, by the processor, counts of documents similar to a reference document for a plurality of similarity ratings, each similarity rating being based on a number of co-occurring terms between the reference document and corresponding similar documents; presenting in a graphical user interface (GUI) the reference document and a GUI element pertaining to the documents similar to the reference document; and upon a selection of the GUI element, presenting in the GUI a second GUI element comprising similarity ratings associated with the reference document; and in response to selecting one of the similarity ratings, presenting in the second GUI element a visual representation of the counts of similar documents that indicate a number of documents that are retrievable based on the selected similarity rating, wherein the visual representation is provided prior to retrieving one of the similar documents. 20. The non-transitory computer readable storage medium of claim 17 , wherein the visual representation is a histogram of the counts of the similar documents for the plurality of similarity ratings.