Before revision:  Since collecting labeled decompositions is cumbersome, we propose an unsupervised approach to produce sub-questions . Specifically, by leveraging >10M questions from Common Crawl, we learn to map from the distribution of multi-hop questions to the distribution of single-hop sub-questions.
After revision:  Since collecting labeled decompositions is cumbersome, we propose an unsupervised approach to produce sub-questions , also enabling us to leverage millions of questions from the internet. Specifically, we propose an algorithm for One-to-N Unsupervised Sequence transduction (ONUS) that learns to map one hard, multi-hop questions to the distribution of single-hop sub-questions.