Minimum Risk Training for Neural Machine Translation
Table 4: Case-insensitive TER scores on Chinese-English translation.
['System', 'Training', 'MT06', 'MT02', 'MT03', 'MT04', 'MT05', 'MT08']
The loss function used in MRT is −sBLEU. MRT still obtains dramatic improvements over Moses and RNNsearch with MLE as the training criterion (up to -10.27 and -8.32 TER points, respectively) across all test sets. All the improvements are statistically significant.