README.md

---
license: mit
datasets:
- wikipedia
- bookcorpus
language:
- en
metrics:
- glue
library_name: transformers
---

This is our reproduction using the official HuggingFace `roberta` architecture with a medium size. On the architecture side, RoBERTa is exactly the same as BERT except for its larger vocabulary size.

According to Google's [BERT releases](https://huggingface.co/google/bert_uncased_L-8_H-512_A-8) and [BERT-Medium](https://huggingface.co/google/bert_uncased_L-8_H-512_A-8/blob/main/config.json), a medium sized model should have a config of Layer=8, Hidden=512, #AttnHeads=8, and IntermediateSize=2048. We follow this config to pre-train a RoBERTa-base model for reproduction.

We use the same datasets as BERT (English Wikipedia and Book Corpus) to pre-train for 30k steps with a batch size of 8,192. I also released the reproduction of this dataset [on HuggingFace](https://huggingface.co/datasets/JackBAI/bert_pretrain_datasets).

We utilized DeepSpeed ZeRO-2 for performance optimization.

Other training configuration: 

| Parameter            | Value     |
|----------------------|-----------|
| WARMUP_STEPS         | 1800      |
| LR_DECAY             | linear    |
| ADAM_EPS             | 1e-6      |
| ADAM_BETA1           | 0.9       |
| ADAM_BETA2           | 0.98      |
| ADAM_WEIGHT_DECAY    | 0.01      |
| PEAK_LR              | 1e-3      |

We achieve very similar performance as the official BERT-Medium release on GLUE:

| Model           | MRPC-F1 | STS-B-Pearson | SST-2-Acc | QQP-F1 | MNLI-m | MNLI-mm | QNLI-Acc | WNLI-Acc | RTE-Acc |
|----------------|---------|---------------|-----------|--------|--------|---------|----------|----------|---------|
| RoBERTa-medium (ours)         |  83.6    | 82.7          | 89.7      | 89.0   | 79.7   | 80.1    | 89.3     | 31.0     | 57.4    |
| [BERT-medium](https://huggingface.co/google/bert_uncased_L-8_H-512_A-8) | 86.3 | 87.7 | 88.9 | 89.4 | 80.6 | 81.0 | 89.2 | 29.6 | 63.9 |

Evaluation Scores Curve (AVG of scores) during pretraining:

![image/png](https://cdn-uploads.huggingface.co/production/uploads/62927c2e56fedc76e396b3ca/p6KK_6-oXCyhAjdZh1WQ_.png)

For both stats above we don't report CoLA scores as it's pretty unstable. The raw CoLA scores are:

| Step     | 1500 | 3000 | 6000 | 9000 | 13500 | 18000 | 24000 | 30000 |
|----------|----------|----------|----------|----------|----------|----------|----------|----------|
CoLA | 1.7 | 13.5 | 29.2 | 31.4 | 31.1 | 24.1 | 29.0 | 20.0 |