Improving Table Retrieval for Open-Domain Question Answering by Considering Join Relationships

Retrieving relevant tables containing the necessary information to accurately answer a given question over tables is critical to open-domain question-answering (QA) systems. However, many questions require retrieving multiple tables and joining them through a join plan that cannot be discerned from the user query itself. The proposed method uncovers useful join relations during table retrieval to improve performance.