A New Approach to Overgenerating and Scoring Abstractive Summaries
This addresses the need for more flexible and faithful abstractive summarization, particularly when space is limited, but it is incremental as it builds on existing summarization methods.
The paper tackles the problem of abstractive summarizers struggling to produce outputs with multiple desirable properties by proposing a two-staged strategy to generate diverse candidate summaries and select admissible ones based on user needs, achieving state-of-the-art performance on benchmark datasets.
We propose a new approach to generate multiple variants of the target summary with diverse content and varying lengths, then score and select admissible ones according to users' needs. Abstractive summarizers trained on single reference summaries may struggle to produce outputs that achieve multiple desirable properties, i.e., capturing the most important information, being faithful to the original, grammatical and fluent. In this paper, we propose a two-staged strategy to generate a diverse set of candidate summaries from the source text in stage one, then score and select admissible ones in stage two. Importantly, our generator gives a precise control over the length of the summary, which is especially well-suited when space is limited. Our selectors are designed to predict the optimal summary length and put special emphasis on faithfulness to the original text. Both stages can be effectively trained, optimized and evaluated. Our experiments on benchmark summarization datasets suggest that this paradigm can achieve state-of-the-art performance.