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arXiv · 2001.04589

Faster Transformer Decoding: N-gram Masked Self-Attention

Ciprian Chelba·Mia Chen·Ankur Bapna·Noam Shazeer
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Abstract

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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Ciprian Chelba, Mia Chen, Ankur Bapna, Noam Shazeer. 2020-01-14. Faster Transformer Decoding: N-gram Masked Self-Attention. https://arxiv.org/abs/2001.04589

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