diff --git a/docs/source/en/model_doc/electra.md b/docs/source/en/model_doc/electra.md index bee883d64153..9506d6dba1c0 100644 --- a/docs/source/en/model_doc/electra.md +++ b/docs/source/en/model_doc/electra.md @@ -14,66 +14,95 @@ rendered properly in your Markdown viewer. --> -# ELECTRA - -
-PyTorch -TensorFlow -Flax +
+ PyTorch + TensorFlow + Flax + SDPA +
-## Overview - -The ELECTRA model was proposed in the paper [ELECTRA: Pre-training Text Encoders as Discriminators Rather Than -Generators](https://openreview.net/pdf?id=r1xMH1BtvB). ELECTRA is a new pretraining approach which trains two -transformer models: the generator and the discriminator. The generator's role is to replace tokens in a sequence, and -is therefore trained as a masked language model. The discriminator, which is the model we're interested in, tries to -identify which tokens were replaced by the generator in the sequence. - -The abstract from the paper is the following: - -*Masked language modeling (MLM) pretraining methods such as BERT corrupt the input by replacing some tokens with [MASK] -and then train a model to reconstruct the original tokens. While they produce good results when transferred to -downstream NLP tasks, they generally require large amounts of compute to be effective. As an alternative, we propose a -more sample-efficient pretraining task called replaced token detection. Instead of masking the input, our approach -corrupts it by replacing some tokens with plausible alternatives sampled from a small generator network. Then, instead -of training a model that predicts the original identities of the corrupted tokens, we train a discriminative model that -predicts whether each token in the corrupted input was replaced by a generator sample or not. Thorough experiments -demonstrate this new pretraining task is more efficient than MLM because the task is defined over all input tokens -rather than just the small subset that was masked out. As a result, the contextual representations learned by our -approach substantially outperform the ones learned by BERT given the same model size, data, and compute. The gains are -particularly strong for small models; for example, we train a model on one GPU for 4 days that outperforms GPT (trained -using 30x more compute) on the GLUE natural language understanding benchmark. Our approach also works well at scale, -where it performs comparably to RoBERTa and XLNet while using less than 1/4 of their compute and outperforms them when -using the same amount of compute.* - -This model was contributed by [lysandre](https://huggingface.co/lysandre). The original code can be found [here](https://github.com/google-research/electra). - -## Usage tips - -- ELECTRA is the pretraining approach, therefore there is nearly no changes done to the underlying model: BERT. The - only change is the separation of the embedding size and the hidden size: the embedding size is generally smaller, - while the hidden size is larger. An additional projection layer (linear) is used to project the embeddings from their - embedding size to the hidden size. In the case where the embedding size is the same as the hidden size, no projection - layer is used. -- ELECTRA is a transformer model pretrained with the use of another (small) masked language model. The inputs are corrupted by that language model, which takes an input text that is randomly masked and outputs a text in which ELECTRA has to predict which token is an original and which one has been replaced. Like for GAN training, the small language model is trained for a few steps (but with the original texts as objective, not to fool the ELECTRA model like in a traditional GAN setting) then the ELECTRA model is trained for a few steps. -- The ELECTRA checkpoints saved using [Google Research's implementation](https://github.com/google-research/electra) - contain both the generator and discriminator. The conversion script requires the user to name which model to export - into the correct architecture. Once converted to the HuggingFace format, these checkpoints may be loaded into all - available ELECTRA models, however. This means that the discriminator may be loaded in the - [`ElectraForMaskedLM`] model, and the generator may be loaded in the - [`ElectraForPreTraining`] model (the classification head will be randomly initialized as it - doesn't exist in the generator). - -## Resources - -- [Text classification task guide](../tasks/sequence_classification) -- [Token classification task guide](../tasks/token_classification) -- [Question answering task guide](../tasks/question_answering) -- [Causal language modeling task guide](../tasks/language_modeling) -- [Masked language modeling task guide](../tasks/masked_language_modeling) -- [Multiple choice task guide](../tasks/multiple_choice) +# ELECTRA + +[ELECTRA](https://huggingface.co/papers/2003.10555) modifies the pretraining objective of traditional masked language models like BERT. Instead of just masking tokens and asking the model to predict them, ELECTRA trains two models, a generator and a discriminator. The generator replaces some tokens with plausible alternatives and the discriminator (the model you'll actually use) learns to detect which tokens are original and which were replaced. This training approach is very efficient and scales to larger models while using considerably less compute. + +This approach is super efficient because ELECTRA learns from every single token in the input, not just the masked ones. That's why even the small ELECTRA models can match or outperform much larger models while using way less computing resources. + +You can find all the original ELECTRA checkpoints under the [ELECTRA](https://huggingface.co/collections/google/electra-release-64ff6e8b18830fabea30a1ab) release. + +> [!TIP] +> Click on the right sidebar for more examples of how to use ELECTRA for different language tasks like sequence classification, token classification, and question answering. + +The example below demonstrates how to classify text with [`Pipeline`] or the [`AutoModel`] class. + + + + +```py +import torch +from transformers import pipeline + +classifier = pipeline( + task="text-classification", + model="bhadresh-savani/electra-base-emotion", + torch_dtype=torch.float16, + device=0 +) +classifier("This restaurant has amazing food!") +``` + + + + +```py +import torch +from transformers import AutoTokenizer, AutoModelForSequenceClassification + +tokenizer = AutoTokenizer.from_pretrained( + "bhadresh-savani/electra-base-emotion", +) +model = AutoModelForSequenceClassification.from_pretrained( + "bhadresh-savani/electra-base-emotion", + torch_dtype=torch.float16 +) +inputs = tokenizer("ELECTRA is more efficient than BERT", return_tensors="pt") + +with torch.no_grad(): + outputs = model(**inputs) + logits = outputs.logits + predicted_class_id = logits.argmax(dim=-1).item() + predicted_label = model.config.id2label[predicted_class_id] +print(f"Predicted label: {predicted_label}") +``` + + + + +```bash +echo -e "This restaurant has amazing food." | transformers-cli run --task text-classification --model bhadresh-savani/electra-base-emotion --device 0 +``` + + + + +## Notes + +- ELECTRA consists of two transformer models, a generator (G) and a discriminator (D). For most downstream tasks, use the discriminator model (as indicated by `*-discriminator` in the name) rather than the generator. +- ELECTRA comes in three sizes: small (14M parameters), base (110M parameters), and large (335M parameters). +- ELECTRA can use a smaller embedding size than the hidden size for efficiency. When `embedding_size` is smaller than `hidden_size` in the configuration, a projection layer connects them. +- When using batched inputs with padding, make sure to use attention masks to prevent the model from attending to padding tokens. + + ```py + # Example of properly handling padding with attention masks + inputs = tokenizer(["Short text", "This is a much longer text that needs padding"], + padding=True, + return_tensors="pt") + outputs = model(**inputs) # automatically uses the attention_mask + ``` + +- When using the discriminator for a downstream task, you can load it into any of the ELECTRA model classes ([`ElectraForSequenceClassification`], [`ElectraForTokenClassification`], etc.). ## ElectraConfig