AskNow: A Framework for Natural Language Query Formalization in SPARQL

  • Mohnish Dubey
  • Sourish Dasgupta
  • Ankit Sharma
  • Konrad Höffner
  • Jens Lehmann
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9678)


Natural Language Query Formalization involves semantically parsing queries in natural language and translating them into their corresponding formal representations. It is a key component for developing question-answering (QA) systems on RDF data. The chosen formal representation language in this case is often SPARQL. In this paper, we propose a framework, called AskNow, where users can pose queries in English to a target RDF knowledge base (e.g. DBpedia), which are first normalized into an intermediary canonical syntactic form, called Normalized Query Structure (NQS), and then translated into SPARQL queries. NQS facilitates the identification of the desire (or expected output information) and the user-provided input information, and establishing their mutual semantic relationship. At the same time, it is sufficiently adaptive to query paraphrasing. We have empirically evaluated the framework with respect to the syntactic robustness of NQS and semantic accuracy of the SPARQL translator on standard benchmark datasets.



This work was supported by a grant from the EU H2020 Framework Programme provided for the project Big Data Europe (GA no. 644564).


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Mohnish Dubey
    • 1
  • Sourish Dasgupta
    • 2
  • Ankit Sharma
    • 3
  • Konrad Höffner
    • 4
  • Jens Lehmann
    • 1
    • 5
  1. 1.Computer Science InstituteUniversity of BonnBonnGermany
  2. 2.DA-IICTGandhinagarIndia
  3. 3.State University of New YorkBuffaloUSA
  4. 4.AKSW GroupUniversity of LeipzigLeipzigGermany
  5. 5.Fraunhofer IAISSankt AugustinGermany

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