  In this report, the technical details of our submission to the EPIC-Kitchens
Action Anticipation Challenge 2021 are given. We developed a hierarchical
attention model for action anticipation, which leverages Transformer-based
attention mechanism to aggregate features across temporal dimension,
modalities, symbiotic branches respectively. In terms of Mean Top-5 Recall of
action, our submission with team name ICL-SJTU achieved 13.39% for overall
testing set, 10.05% for unseen subsets and 11.88% for tailed subsets.
Additionally, it is noteworthy that our submission ranked 1st in terms of verb
class in all three (sub)sets.
