ProphetNet

This model was released on 2020-01-13 and added to Hugging Face Transformers on 2020-11-16.

ProphetNet

Overview

The ProphetNet model was proposed in ProphetNet: Predicting Future N-gram for Sequence-to-Sequence Pre-training, by Yu Yan, Weizhen Qi, Yeyun Gong, Dayiheng Liu, Nan Duan, Jiusheng Chen, Ruofei Zhang, Ming Zhou on 13 Jan, 2020.

ProphetNet is an encoder-decoder model and can predict n-future tokens for “ngram” language modeling instead of just the next token.

The abstract from the paper is the following:

In this paper, we present a new sequence-to-sequence pretraining model called ProphetNet, which introduces a novel self-supervised objective named future n-gram prediction and the proposed n-stream self-attention mechanism. Instead of the optimization of one-step ahead prediction in traditional sequence-to-sequence model, the ProphetNet is optimized by n-step ahead prediction which predicts the next n tokens simultaneously based on previous context tokens at each time step. The future n-gram prediction explicitly encourages the model to plan for the future tokens and prevent overfitting on strong local correlations. We pre-train ProphetNet using a base scale dataset (16GB) and a large scale dataset (160GB) respectively. Then we conduct experiments on CNN/DailyMail, Gigaword, and SQuAD 1.1 benchmarks for abstractive summarization and question generation tasks. Experimental results show that ProphetNet achieves new state-of-the-art results on all these datasets compared to the models using the same scale pretraining corpus.

The Authors’ code can be found here.

Usage tips

• ProphetNet is a model with absolute position embeddings so it’s usually advised to pad the inputs on the right rather than the left.
• The model architecture is based on the original Transformer, but replaces the “standard” self-attention mechanism in the decoder by a main self-attention mechanism and a self and n-stream (predict) self-attention mechanism.

Resources

• Causal language modeling task guide
• Translation task guide
• Summarization task guide

ProphetNetConfig

[[autodoc]] ProphetNetConfig

ProphetNetTokenizer

[[autodoc]] ProphetNetTokenizer

ProphetNet specific outputs

[[autodoc]] models.prophetnet.modeling_prophetnet.ProphetNetSeq2SeqLMOutput

[[autodoc]] models.prophetnet.modeling_prophetnet.ProphetNetSeq2SeqModelOutput

[[autodoc]] models.prophetnet.modeling_prophetnet.ProphetNetDecoderModelOutput

[[autodoc]] models.prophetnet.modeling_prophetnet.ProphetNetDecoderLMOutput

ProphetNetModel

[[autodoc]] ProphetNetModel - forward

ProphetNetEncoder

[[autodoc]] ProphetNetEncoder - forward

ProphetNetDecoder

[[autodoc]] ProphetNetDecoder - forward

ProphetNetForConditionalGeneration

[[autodoc]] ProphetNetForConditionalGeneration - forward

ProphetNetForCausalLM

[[autodoc]] ProphetNetForCausalLM - forward