A dedicated son brings Fenway Park to his dad's backyard Michael Bisono built a little slice of Boston for his father Antonio-without any construction experience. Michael Bisono of Cranston, Rhode Island built this backyard version of Fenway Park for his father, Antonio. Breakthroughs, discoveries, and DIY tips sent every weekday. Antonio and Michael Bisono don't let one of sports' oldest and most historic rivalries get in the way of their bond as father and son. Like the "magic mud" that lines baseballs themselves, the sport helps hold them together.

Different entities with the same name can be difficult to distinguish. Handling confusing entity mentions is a crucial skill for language models (LMs). For example, given the question "Where was Michael Jordan educated?" and a set of documents discussing different people named Michael Jordan, can LMs distinguish entity mentions to generate a cohesive answer to the question? To test this ability, we introduce a new benchmark, AmbigDocs. By leveraging Wikipedia's disambiguation pages, we identify a set of documents, belonging to different entities who share an ambiguous name. From these documents, we generate questions containing an ambiguous name and their corresponding sets of answers. Our analysis reveals that current state-of-the-art models often yield ambiguous answers or incorrectly merge information belonging to different entities. We establish an ontology categorizing four types of incomplete answers and automatic evaluation metrics to identify such categories. We lay the foundation for future work on reasoning across multiple documents with ambiguous entities.