Outlining and Filling: Hierarchical Query Graph Generation for Answering Complex Questions over Knowledge Graphs. (arXiv:2111.00732v2 [cs.AI] UPDATED)

Query graph construction aims to construct the correct executable SPARQL on
the KG to answer natural language questions. Although recent methods have
achieved good results using neural network-based query graph ranking, they
suffer from three new challenges when handling more complex questions: 1)
complicated SPARQL syntax, 2) huge search space, and 3) locally ambiguous query
graphs. In this paper, we provide a new solution. As a preparation, we extend
the query graph by treating each SPARQL clause as a subgraph …

arxiv graph graphs hierarchical knowledge knowledge graphs query