We encourage W to perform correct word alignment so that the denoised translated sentences are fluent and grammatically correct.
the training objective is to minimize the negative expected reward, which is formulated as follows: where z t is the output of denoising auto-encoder with t as the input, R(z t ) is the reward evaluating the fluency of z t , and p(t|s) is the probability of W outputs t by performing word-to-word translation on s. We introduce them in detail as follows.