APANTISIS: A Greek Question-Answering System for Knowledge-Base Exploration

  • Emmanouil Marakakis
  • Haridimos KondylakisEmail author
  • Papakonstantinou Aris
Conference paper
Part of the Springer Proceedings in Business and Economics book series (SPBE)


As users struggle to navigate on the vast amount of information now available, methods and tools for enabling the quick exploration of the databases content is of paramount importance. To this direction we present Apantisis, a novel question answering system implemented for the Greek language ready to be attached to any external database/knowledge-base. An ingestion module enables the semi/automatic construction of the data dictionary that is used for question answering whereas the Greek Language Dictionary, the Syntactic and the Semantic Rules are also stored in an internal, extensible knowledge base. After the ingestion phase, the system is accepting questions in natural language, and automatically constructs the corresponding relational algebra query to be further evaluated by the external database. The results are then formulated as free text and returned to the user. We highlight the unique features of our system with respect to the Greek language and we present its implementation and a preliminary evaluation. Finally, we argue that our solution is flexible and modular and can be used for improving the usability of traditional database systems.


Natural Language Relational Algebra Parse Tree Query Answering Data Dictionary 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Emmanouil Marakakis
    • 1
  • Haridimos Kondylakis
    • 2
    Email author
  • Papakonstantinou Aris
    • 1
  1. 1.Department of Informatics EngineeringTechnological Educational Institute of CreteHeraklionGreece
  2. 2.Computational Biomedicine LaboratoryHeraklionGreece

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