AligNART: Non-autoregressive Neural Machine Translation by Jointly
Learning to Estimate Alignment and Translate
- URL: http://arxiv.org/abs/2109.06481v1
- Date: Tue, 14 Sep 2021 07:26:33 GMT
- Title: AligNART: Non-autoregressive Neural Machine Translation by Jointly
Learning to Estimate Alignment and Translate
- Authors: Jongyoon Song, Sungwon Kim, and Sungroh Yoon
- Abstract summary: AligNART uses alignment information to reduce the modality of the target distribution.
AligNART effectively addresses the token repetition problem even without sequence-level knowledge distillation.
- Score: 20.980671405042756
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Non-autoregressive neural machine translation (NART) models suffer from the
multi-modality problem which causes translation inconsistency such as token
repetition. Most recent approaches have attempted to solve this problem by
implicitly modeling dependencies between outputs. In this paper, we introduce
AligNART, which leverages full alignment information to explicitly reduce the
modality of the target distribution. AligNART divides the machine translation
task into $(i)$ alignment estimation and $(ii)$ translation with aligned
decoder inputs, guiding the decoder to focus on simplified one-to-one
translation. To alleviate the alignment estimation problem, we further propose
a novel alignment decomposition method. Our experiments show that AligNART
outperforms previous non-iterative NART models that focus on explicit modality
reduction on WMT14 En$\leftrightarrow$De and WMT16 Ro$\rightarrow$En.
Furthermore, AligNART achieves BLEU scores comparable to those of the
state-of-the-art connectionist temporal classification based models on WMT14
En$\leftrightarrow$De. We also observe that AligNART effectively addresses the
token repetition problem even without sequence-level knowledge distillation.
Related papers
- Fuzzy Alignments in Directed Acyclic Graph for Non-Autoregressive
Machine Translation [18.205288788056787]
Non-autoregressive translation (NAT) reduces the decoding latency but suffers from performance degradation due to the multi-modality problem.
In this paper, we hold the view that all paths in the graph are fuzzily aligned with the reference sentence.
We do not require the exact alignment but train the model to maximize a fuzzy alignment score between the graph and reference, which takes translations captured in all modalities into account.
arXiv Detail & Related papers (2023-03-12T13:51:38Z) - Categorizing Semantic Representations for Neural Machine Translation [53.88794787958174]
We introduce categorization to the source contextualized representations.
The main idea is to enhance generalization by reducing sparsity and overfitting.
Experiments on a dedicated MT dataset show that our method reduces compositional generalization error rates by 24% error reduction.
arXiv Detail & Related papers (2022-10-13T04:07:08Z) - Non-Autoregressive Neural Machine Translation: A Call for Clarity [3.1447111126465]
We take a step back and revisit several techniques that have been proposed for improving non-autoregressive translation models.
We provide novel insights for establishing strong baselines using length prediction or CTC-based architecture variants.
We contribute standardized BLEU, chrF++, and TER scores using sacreBLEU on four translation tasks.
arXiv Detail & Related papers (2022-05-21T12:15:22Z) - Anticipation-free Training for Simultaneous Translation [70.85761141178597]
Simultaneous translation (SimulMT) speeds up the translation process by starting to translate before the source sentence is completely available.
Existing methods increase latency or introduce adaptive read-write policies for SimulMT models to handle local reordering and improve translation quality.
We propose a new framework that decomposes the translation process into the monotonic translation step and the reordering step.
arXiv Detail & Related papers (2022-01-30T16:29:37Z) - Contrastive Learning for Context-aware Neural Machine TranslationUsing
Coreference Information [14.671424999873812]
We propose CorefCL, a novel data augmentation and contrastive learning scheme based on coreference between the source and contextual sentences.
By corrupting automatically detected coreference mentions in the contextual sentence, CorefCL can train the model to be sensitive to coreference inconsistency.
In experiments, our method consistently improved BLEU of compared models on English-German and English-Korean tasks.
arXiv Detail & Related papers (2021-09-13T05:18:47Z) - Improving Multilingual Translation by Representation and Gradient
Regularization [82.42760103045083]
We propose a joint approach to regularize NMT models at both representation-level and gradient-level.
Our results demonstrate that our approach is highly effective in both reducing off-target translation occurrences and improving zero-shot translation performance.
arXiv Detail & Related papers (2021-09-10T10:52:21Z) - Exploring Unsupervised Pretraining Objectives for Machine Translation [99.5441395624651]
Unsupervised cross-lingual pretraining has achieved strong results in neural machine translation (NMT)
Most approaches adapt masked-language modeling (MLM) to sequence-to-sequence architectures, by masking parts of the input and reconstructing them in the decoder.
We compare masking with alternative objectives that produce inputs resembling real (full) sentences, by reordering and replacing words based on their context.
arXiv Detail & Related papers (2021-06-10T10:18:23Z) - Modeling Coverage for Non-Autoregressive Neural Machine Translation [9.173385214565451]
We propose a novel Coverage-NAT to model the coverage information directly by a token-level coverage iterative refinement mechanism and a sentence-level coverage agreement.
Experimental results on WMT14 En-De and WMT16 En-Ro translation tasks show that our method can alleviate those errors and achieve strong improvements over the baseline system.
arXiv Detail & Related papers (2021-04-24T07:33:23Z) - Incorporating BERT into Parallel Sequence Decoding with Adapters [82.65608966202396]
We propose to take two different BERT models as the encoder and decoder respectively, and fine-tune them by introducing simple and lightweight adapter modules.
We obtain a flexible and efficient model which is able to jointly leverage the information contained in the source-side and target-side BERT models.
Our framework is based on a parallel sequence decoding algorithm named Mask-Predict considering the bi-directional and conditional independent nature of BERT.
arXiv Detail & Related papers (2020-10-13T03:25:15Z) - LAVA NAT: A Non-Autoregressive Translation Model with Look-Around
Decoding and Vocabulary Attention [54.18121922040521]
Non-autoregressive translation (NAT) models generate multiple tokens in one forward pass.
These NAT models often suffer from the multimodality problem, generating duplicated tokens or missing tokens.
We propose two novel methods to address this issue, the Look-Around (LA) strategy and the Vocabulary Attention (VA) mechanism.
arXiv Detail & Related papers (2020-02-08T04:11:03Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.