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Faster Transformer Decoding: N-gram Masked Self-Attention

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 Added by Ciprian Chelba
 Publication date 2020
and research's language is English




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Motivated by the fact that most of the information relevant to the prediction of target tokens is drawn from the source sentence $S=s_1, ldots, s_S$, we propose truncating the target-side window used for computing self-attention by making an $N$-gram assumption. Experiments on WMT EnDe and EnFr data sets show that the $N$-gram masked self-attention model loses very little in BLEU score for $N$ values in the range $4, ldots, 8$, depending on the task.



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