19. A system, comprising: a selection mechanism configured to select a collection of documents which includes a first set of passages; a passage-sequence model construction mechanism configured to construct a passage-sequence model based on the first set of passages, wherein the passage-sequence model is a hidden Markov model (HMM), wherein the passage-sequence model construction mechanism is further configured to determine transition probabilities between states of the HMM based on a sequential relationship associated with the first set of passages; a receiving mechanism configured to receive a new document which includes a second set of passages; and a determination mechanism configured to determine a sequence of operations associated with the new document in relation to the collection of documents based on the constructed passage-sequence model.
19. A system, comprising: a selection mechanism configured to select a collection of documents which includes a first set of passages; a passage-sequence model construction mechanism configured to construct a passage-sequence model based on the first set of passages, wherein the passage-sequence model is a hidden Markov model (HMM), wherein the passage-sequence model construction mechanism is further configured to determine transition probabilities between states of the HMM based on a sequential relationship associated with the first set of passages; a receiving mechanism configured to receive a new document which includes a second set of passages; and a determination mechanism configured to determine a sequence of operations associated with the new document in relation to the collection of documents based on the constructed passage-sequence model. 20. The system of claim 19 , further comprising a similarity-estimation mechanism configured to estimate a similarity between the new document and at least one document within the collection based on the determined sequence of operations.