Reviews: Language as an Abstraction for Hierarchical Deep Reinforcement Learning

I believe the proposed method, HAL (Hierarchical Abstraction with Language), is an interesting approach for HRL. The authors adapt Hindsight Experience Replay for instructions (called Hindsight Instruction Relabelling). I have some concerns about the experimental setup and empirical evaluation of the proposed method: - The motivation behind introducing a new environment is unclear. There are a lot of similar existing environments such as crafting environment used by [1], compositional and relational navigation environment in [2]. Introducing a new environment (unless its necessary) hinders proper comparison and benchmarking.