task_categories:question-answering task_ids:open-domain-qa annotations_creators:expert-generated language_creators:crowdsourced multilinguality:monolingual source_datasets:extended|ms_marco language:en license:cc-by-4.0 size_categories:100K<n<1M format:parquet modality:text library:datasets library:dask library:mlcroissant library:polars arxiv:1611.09268 region:us msmarco natural language generation question answering