Scoring Sentence Singletons and Pairs for Abstractive Summarization
This work addresses a specific bottleneck in abstractive summarization for NLP researchers, but it is incremental as it builds on existing methods without introducing a new paradigm.
The paper tackles the gap between sentence selection and fusion in abstractive summarization by ranking both single sentences and sentence pairs in a unified framework, achieving results that show improvements in ROUGE scores on standard datasets.
When writing a summary, humans tend to choose content from one or two sentences and merge them into a single summary sentence. However, the mechanisms behind the selection of one or multiple source sentences remain poorly understood. Sentence fusion assumes multi-sentence input; yet sentence selection methods only work with single sentences and not combinations of them. There is thus a crucial gap between sentence selection and fusion to support summarizing by both compressing single sentences and fusing pairs. This paper attempts to bridge the gap by ranking sentence singletons and pairs together in a unified space. Our proposed framework attempts to model human methodology by selecting either a single sentence or a pair of sentences, then compressing or fusing the sentence(s) to produce a summary sentence. We conduct extensive experiments on both single- and multi-document summarization datasets and report findings on sentence selection and abstraction.