This is done by evaluating state-of-theart models on our task and evaluating the effects of providing additional grounding.
we adapt the BERT contextual language model (Devlin et al., 2018) to the task of dialogue in two ways: as a bi-ranker, which is fast and practical as a retrieval model, and as a cross-ranker which is slower at inference time but allows more feature cross-correlation between context and response.