Hybrid graph based keyword query interpretation on RDF

Adopting keyword query interface to semantic search on RDF data can help users keep away from learning the SPARQL query syntax and understanding the complex and fast evolving data schema. The existing approaches are divided into two categories: instance-based approaches and schema-based approaches. The instance-based approaches relying on the original RDF graph can generate precise answers but take a long processing time. In contrast, the schema-based approaches relying on the reduced summary graph require much less processing time but cannot always generate correct answers. In this paper, we propose a novel approach based on a hybrid graph which can achieve significant improvements on processing time with a limited accuracy drop compared with instance-based approaches, and meanwhile, can achieve promising accuracy gains at an affordable time cost compared with schema-based approaches.