1. A method of ranking a document cluster which includes two or more documents, the method comprising: obtaining, at a document cluster ranking system, a value associated with a first feature for each of a plurality of document clusters; based on the values associated with the first feature, automatically generating, at the document cluster ranking system, for each of a plurality of first feature bins, a range of values and a bin identifier to define each of the plurality of first feature bins; and obtaining a score for one of the document clusters, by: identifying the first feature bin having a range of values which includes the obtained value associated with the first feature for that one of the document clusters; and determining a score for that document cluster based on the first feature bin identifier for the identified first feature bin.
7. The method of claim 1 , further comprising: obtaining, at a document cluster ranking system, a value associated with a second feature for each of a plurality of document clusters; based on the values associated with the second feature, automatically generating, at the document cluster ranking system, for each of a plurality of second feature bins, a range of values and a bin identifier to define each of the plurality of second feature bins, and wherein obtaining a score for one of the document clusters further comprises: identifying the second feature bin having a range of values which includes the obtained value associated with the second feature for that one of the document clusters; and determining the score for that document cluster based on the bin identifier for the identified second feature bin.