16. An active learning training system that a user can interact with, comprising: a translation module for translating a test set E from a first collection to a second collection using a unidirectional translation corpus and from the second collection to the first collection using a unidirectional translation corpus so as to create a set E′ in the first collection, wherein differences between E and E′ are determined; a comparison module for computing confidence scores for a translation of each item in the test set E based on a similarity of E and E′ and adding translations to a parallel corpus based on the confidence scores; and memory storage for storing a created or updated parallel corpus.
16. An active learning training system that a user can interact with, comprising: a translation module for translating a test set E from a first collection to a second collection using a unidirectional translation corpus and from the second collection to the first collection using a unidirectional translation corpus so as to create a set E′ in the first collection, wherein differences between E and E′ are determined; a comparison module for computing confidence scores for a translation of each item in the test set E based on a similarity of E and E′ and adding translations to a parallel corpus based on the confidence scores; and memory storage for storing a created or updated parallel corpus. 19. The system as recited in claim 16 , further comprising a user interface that includes a Graphical User Interface displaying at least controls for changing features to compute the confidence scores, the features being at least one of a scoring metric and values used to create subsets of low and high confidence machine translations.