Towards Reinforcement Learning for Pivot-based Neural Machine Translation with Non-autoregressive Transformer

Pivot-based neural machine translation (NMT) is commonly used in low-resource setups, especially for translation between non-English language pairs. It benefits from using high-resource source-to-pivot and pivot-to-target language pairs and an individual system is trained for both sub-tasks. However, these models have no connection during training, and the source-to-pivot model is not optimized to produce the best translation for the source-to-target task. In this work, we propose to train a pivot-based NMT system with the reinforcement learning (RL) approach, which has been investigated for various text generation tasks, including machine translation (MT). We utilize a non-autoregressive transformer and present an end-to-end pivot-based integrated model, enabling training on source-to-target data.