DRAGON+ is a BERT-base sized dense retriever initialized from RetroMAE and further trained on the data augmented from MS MARCO corpus, following the approach described in How to Train Your DRAGON:
Diverse Augmentation Towards Generalizable Dense Retrieval.

The associated GitHub repository is available here https://github.com/facebookresearch/dpr-scale/tree/main/dragon. We use asymmetric dual encoder, with two distinctly parameterized encoders. The following models are also available: