Thank you for your in-depth and constructive reviews, they will give us an excellent chance to further improve the paper

Thank you for your in-depth and constructive reviews, they will give us an excellent chance to further improve the paper. We address the reviewers concerns individually below. Minor Concerns: We will address these concerns in the revision. Empirically, then, it makes sense to compare to other mini-batch methods, like IS. 'mean' is the correct one. For O1, you are correct in your understanding.