1. A method for comparing and optionally recommending works of literature, the method comprising: accessing by a processor a first cluster model for a first work of literature; accessing by a processor at least a second cluster model for at least a second work of literature; comparing by a processor the first and at least second cluster models for similarities; generating by a processor a score according to degrees of match between the first and second cluster models; and producing by a processor a recommendation score regarding the second work of literature as being comparable or similar to the first work of literature; wherein the first and second cluster models reflect clusters of concepts and longitudinal trends of elements in the clusters across multiple segments contained entirely within each respective work of literature.