Template-Based Question Answering over Linked Geospatial Data

Dharmen Punjani; Markos Iliakis; Theodoros Stefou; Kuldeep Singh; Andreas Both; Manolis Koubarakis; Iosif Angelidis; Konstantina Bereta; Themis Beris; Dimitris Bilidas; Theofilos Ioannidis; Nikolaos Karalis; Christoph Lange; Despina-Athanasia Pantazi; Christos Papaloukas; Georgios Stamoulis

arXiv · 2007.07060

Template-Based Question Answering over Linked Geospatial Data

Dharmen Punjani·Markos Iliakis·Theodoros Stefou·Kuldeep Singh·Andreas Both·Manolis Koubarakis·Iosif Angelidis·Konstantina Bereta·Themis Beris·Dimitris Bilidas·Theofilos Ioannidis·Nikolaos Karalis·Christoph Lange·Despina-Athanasia Pantazi·Christos Papaloukas·Georgios Stamoulis

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Abstract

Large amounts of geospatial data have been made available recently on the linked open data cloud and the portals of many national cartographic agencies (e.g., OpenStreetMap data, administrative geographies of various countries, or land cover/land use data sets). These datasets use various geospatial vocabularies and can be queried using SPARQL or its OGC-standardized extension GeoSPARQL. In this paper, we go beyond these approaches to offer a question-answering engine for natural language questions on top of linked geospatial data sources. Our system has been implemented as re-usable components of the Frankenstein question answering architecture. We give a detailed description of the system's architecture, its underlying algorithms, and its evaluation using a set of 201 natural language questions. The set of questions is offered to the research community as a gold standard dataset for the comparative evaluation of future geospatial question answering engines.

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Dharmen Punjani, Markos Iliakis, Theodoros Stefou, Kuldeep Singh, Andreas Both, Manolis Koubarakis, Iosif Angelidis, Konstantina Bereta, Themis Beris, Dimitris Bilidas, Theofilos Ioannidis, Nikolaos Karalis, Christoph Lange, Despina-Athanasia Pantazi, Christos Papaloukas, Georgios Stamoulis. 2020-07-14. Template-Based Question Answering over Linked Geospatial Data. https://arxiv.org/abs/2007.07060

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