Sketching as a Tool for Understanding and Accelerating Self-attention for Long Sequences

Autor: Chen, Y., Qi Zeng, Hakkani-Tur, D., Jin, D., Ji, H., Yang, Y.
Rok vydání: 2021
Předmět:
Zdroj: Web of Science
Scopus-Elsevier
DOI: 10.48550/arxiv.2112.05359
Popis: Transformer-based models are not efficient in processing long sequences due to the quadratic space and time complexity of the self-attention modules. To address this limitation, Linformer and Informer are proposed to reduce the quadratic complexity to linear (modulo logarithmic factors) via low-dimensional projection and row selection respectively. These two models are intrinsically connected, and to understand their connection, we introduce a theoretical framework of matrix sketching. Based on the theoretical analysis, we propose Skeinformer to accelerate self-attention and further improve the accuracy of matrix approximation to self-attention with three carefully designed components: column sampling, adaptive row normalization and pilot sampling reutilization. Experiments on the Long Range Arena (LRA) benchmark demonstrate that our methods outperform alternatives with a consistently smaller time/space footprint.
Databáze: OpenAIRE