Fix typo

README.md

@@ -120,7 +120,7 @@ We follow the original English BERT model's hyperparameters for pre-training, un
 - We used Hugging Face's transformers to fine-tune our CAMeLBERT models.
 - We used transformers `v3.1.0` along with PyTorch `v1.5.1`.
 - The fine-tuning was done by adding a fully connected linear layer to the last hidden state.
-- We use \\(F_{1})\\ score as a metric for all tasks.
+- We use \\(F_{1}\\) score as a metric for all tasks.
 - Code used for fine-tuning is available [here](https://github.com/CAMeL-Lab/CAMeLBERT).
 
 ### Results