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In a world of proliferating data, the abil- ity to rapidly summarize text is grow- ing in importance. Automatic summariza- tion of text can be thought of as a se- quence to sequence problem. Another area of natural language processing that solves a sequence to sequence problem is ma- chine translation, which is rapidly evolv- ing due to the development of attention- based encoder-decoder networks. This work applies these modern techniques to abstractive summarization. We perform analysis on various attention mechanisms for summarization with the goal of devel- oping an approach and architecture aimed at improving the state of the art. In par- ticular, we modify and optimize a trans- lation model with self-attention for gener- ating abstractive sentence summaries. The effectiveness of this base model along with attention variants is compared and ana- lyzed in the context of standardized eval- uation sets and test metrics. However, we show that these metrics are limited in their ability to effectively score abstractive summaries, and propose a new approach based on the intuition that an abstractive model requires an abstractive evaluation.
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Deep Reinforcement Learning for Sequence-to-Sequence Models
In recent times, sequence-to-sequence (seq2seq) models have gained a lot of popularity and provide stateof-the-art performance in a wide variety of tasks, such as machine translation, headline generation, text summarization, speech-to-text conversion, and image caption generation. The underlying framework for all these models is usually a deep neural network comprising an encoder and a decoder. Although simple encoder–decoder models produce competitive results, many researchers have proposed additional improvements over these seq2seq models, e.g., using an attention-based model over the input, pointer-generation models, and self-attention models. However, such seq2seq models suffer from two common problems: 1) exposure bias and 2) inconsistency between train/test measurement. Recently, a completely novel point of view has emerged in addressing these two problems in seq2seq models, leveraging methods from reinforcement learning (RL). In this survey, we consider seq2seq problems from the RL point of view and provide a formulation combining the power of RL methods in decision-making with seq2seq models that enable remembering long-term memories. We present some of the most recent frameworks that combine the concepts from RL and deep neural networks. Our work aims to provide insights into some of the problems that inherently arise with current approaches and how we can address them with better RL models. We also provide the source code for implementing most of the RL models discussed in this paper to support the complex task of abstractive text summarization and provide some targeted experiments for these RL models, both in terms of performance and training time.
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- PAR ID:
- 10142308
- Date Published:
- Journal Name:
- IEEE Transactions on Neural Networks and Learning Systems
- ISSN:
- 2162-237X
- Page Range / eLocation ID:
- 1 to 21
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TNNLS.2019.2929141
