ACL2021

ReadOnce Transformers: Reusable Representations of Text for Transformers

Shih-Ting Lin, Ashish Sabharwal, Tushar Khot

Abstract

We present READONCE Transformers, an approach to convert a transformer-based model into one that can build an informationcapturing, task-independent, and compressed representation of text. The resulting representation is reusable across different examples and tasks, thereby requiring a document shared across many examples or tasks to only be read once. This leads to faster training and evaluation of models. Additionally, we extend standard text-to-text transformer models to Representation+Text-to-text models, and evaluate on multiple downstream tasks: multihop QA, abstractive QA, and long-document summarization. Our one-time computed representation results in a 2x-5x speedup compared to standard text-to-text models, while the compression also allows existing language models to handle longer documents without the need for designing new pre-trained models. 1 * The author's work was primarily done during an internship at the Allen Institute for AI.