Multi-level shared-weight encoding for abstractive sentence summarization

Features in a text are hierarchically structured and may not be optimally learned using one-step encoding. Scrutinizing the literature several times facilitates a better understanding of content and helps frame faithful context representations. The proposed model encapsulates the idea of re-examining a piece of text multiple times to grasp the underlying theme and aspects of English grammar before formulating a summary. We suggest a multi-level shared-weight encoder (MSE) that exclusively focuses on the sentence summarization task. MSE exercises a weight-sharing mechanism for proficiently regulating the multi-level encoding process. Weight-sharing helps recognize patterns left undiscovered by single level encoding strategy. We perform experiments with six encoding levels with weight sharing on the renowned short sentence summarization Gigaword and DUC2004 Task1 datasets. The experiments show that MSE generates a more readable(fluent) summary (Rouge-L score) as compared to multiple benchmark models while preserving similar levels of informativeness (Rouge-1 and Rouge-2 scores). Moreover, human evaluation of the generated abstracts also corroborates these assertions of enhanced readability. © 2021, The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.