Large-scale Pretraining for Visual Dialog: A Simple State-of-the-Art Baseline
Abstract
Prior work in visual dialog has focused on training deep neural models on VisDial in isolation. Instead, we present an approach to leverage pretraining on related vision-language datasets before transferring to visual dialog. We adapt the recently proposed ViLBERT model for multi-turn visually-grounded conversations. Our model is pretrained on the Conceptual Captions and Visual Question Answering datasets, and finetuned on VisDial. Our best single model outperforms prior published work by > 1% absolute on NDCG and MRR.
Next, we find that additional finetuning using “dense” annotations in VisDial leads to even higher NDCG – more than 10% over our base model – but hurts MRR – more than 17% below our base model! This highlights a trade-off between the two primary metrics – NDCG and MRR – which we find is due to dense annotations not correlating well with the original ground-truth answers to questions.