The NLP Task Effectiveness of Long-Range Transformers [article]

Guanghui Qin, Yukun Feng, Benjamin Van Durme
2022 arXiv   pre-print
Transformer models cannot easily scale to long sequences due to their O(N^2) time and space complexity. This has led to Transformer variants seeking to lessen computational complexity, such as Longformer and Performer. While such models have theoretically greater efficiency, their effectiveness on real NLP tasks has not been well studied. We benchmark 7 variants of Transformer models on 5 difficult NLP tasks and 7 datasets. We design experiments to isolate the effect of pretraining and
more » ... meter settings, to focus on their capacity for long-range attention. Moreover, we present various methods to investigate attention behaviors, to illuminate model details beyond metric scores. We find that attention of long-range transformers has advantages on content selection and query-guided decoding, but they come with previously unrecognized drawbacks such as insufficient attention to distant tokens.
arXiv:2202.07856v1 fatcat:pmrm3ogiofgt3cqlysek6wppq4