Liliang Ren, Zixuan Zhang, Han Wang, Clare R. Voss, ChengXiang Zhai, Heng Ji
Modern large-scale Pre-trained Language Models (PLMs) have achieved tremendous success on a wide range of downstream tasks. However, most of the LM pre-training objectives only focus on text reconstruction, but have not sought to learn latent-level interpretable representations of sentences. In this paper, we manage to push the language models to obtain a deeper understanding of sentences by proposing a new pre-training objective, Sparse Latent Typing, which enables the model to sparsely extract sentence-level keywords with diverse latent types. Experimental results show that our model is able to learn interpretable latent type categories in a self-supervised manner without using any external knowledge. Besides, the language model pre-trained with such an objective also significantly improves Information Extraction related downstream tasks in both supervised and few-shot settings. Our code is publicly available at: https://github.com/renll/SparseLT.
| Task | Dataset | Metric | Value | Model |
|---|---|---|---|---|
| Named Entity Recognition (NER) | Few-NERD (INTRA) | 10 way 1~2 shot | 40.48 | BERT-SparseLT+CONTainNER |
| Named Entity Recognition (NER) | Few-NERD (INTRA) | 10 way 5~10 shot | 53.04 | BERT-SparseLT+CONTainNER |
| Named Entity Recognition (NER) | Few-NERD (INTRA) | 5 way 1~2 shot | 47.2 | BERT-SparseLT+CONTainNER |
| Named Entity Recognition (NER) | Few-NERD (INTRA) | 5 way 5~10 shot | 59.67 | BERT-SparseLT+CONTainNER |
| Named Entity Recognition (NER) | Few-NERD (INTER) | 10 way 1~2 shot | 52.75 | BERT-SparseLT + CONTaiNER |
| Named Entity Recognition (NER) | Few-NERD (INTER) | 10 way 5~10 shot | 62.43 | BERT-SparseLT + CONTaiNER |
| Named Entity Recognition (NER) | Few-NERD (INTER) | 5 way 1~2 shot | 57.14 | BERT-SparseLT + CONTaiNER |
| Named Entity Recognition (NER) | Few-NERD (INTER) | 5 way 5~10 shot | 66.17 | BERT-SparseLT + CONTaiNER |