Dr Stefano De Sabbata

 Dr Stefano De Sabbata

Stefano De Sabbata's research focuses on Internet and information geographies, as well as on geographic and mobile information retrieval.


Stefano's work at the Oxford Internet Institute focuses on the analysis and visualisation of the geographies of the Internet. The project aims to study the contemporary geographies of knowledge and the ways that those information landscapes are changing over time. In particular, he is interested in studying how geography influences information access, production, and representation, and how geographic places are discussed and represented on the Internet.

Stefano's PhD project at GIVA unit of the University of Zurich aimed to develop a generic approach to the abstract problem of the assessment of Geographic Relevance. This is a rather recent concept that can be defined as a quality of an entity in geographic space or its representation in an information system, i.e. an object, document, or image. This quality is expressed as the relation between an entity (or its representation) and the actual context of using the representation. More pragmatically, Geographic Relevance aims to assess the relevance of an object that is a representation of a geographic entity within a computer system or information database. This object can be a collection of documents or an entry in a database describing a point of interest. Still, even if the object is a single document, the objective is to approximate the relevance of the entity, not to judge the relevance of a geo-referenced document or a document reporting geographic information. Considering this facet, Geographic Relevance is rather far from the current understanding that underlies Geographic IR, Mobile IR and IR systems in general.

Research interests

Internet geographies, geographic relevance, information retrieval, location-based services, data mining

Positions held at the OII

  • Research Associate, October 2015 -
  • Researcher, May 2013 - September 2015


Current projects



  • Graham, M. and De Sabbata, S. (2016) Mapping Information Wealth and Poverty: The Geography of Gazetteers. Environment and Planning A.
  • De Sabbata, S., Mizzaro, S., and Reichenbacher, T. (2014) Geographic dimensions of relevance. Journal of Documentation.
  • De Sabbata, S. and Reichenbacher, T. (2012) Criteria of geographic relevance: an experimental study. International Journal of Geographical Information Science 26 (8) 1495-1520.
  • Reichenbacher, T. and De Sabbata, S. (2011) Geographic relevance - different notions of geographies and relevancies. SIGSPATIAL special issue on Geographic Information Retrieval 3 (2) 2011.


  • De Sabbata, S., Mizzaro, S., and Vassena, L. (2009) Where do you roll today? Trajectory prediction by SpaceRank and Physics Models. In: Location Based Services and TeleCartography II, Lecture Notes in Geoinformation and Cartography, Springer Berlin Heidelberg, pp. 63-78.

Conference papers

  • De Sabbata, S., Çöltekin, A., Eccles, K., Hale, S. and Straumann, R.K. (2015) Collaborative Visualizations for Wikipedia Critique and Activism. Proceedings of ICWSM. AAAI.
  • De Sabbata, S., and Reichenbacher, T. (2014) Computing geographic relevance in mobile information services. Proceedings of the 1st International Workshop on Context-Awareness in Geographic Information Services (CAGIS 2014). Vienna, Austria, 2014.
  • De Sabbata, S., Alonso, O., and Mizzaro, S. (2012) Classical vs. Crowd-sourcing Surveys for Eliciting Geographic Relevance Criteria. Proceedings of the 3rd Italian Information Retrieval (IIR) workshop. Bari, Italy, 26-27 January 2012.
  • Kuhn, M., Pfister, S., Vontobel, I., Willi, C., De Sabbata, S., and Çöltekin, A. (2011) TIMELINE: A Tool for the Video Analysis and Visualisation of Geographic Phenomena over Time. Proceedings of 25th International Cartographic Conference, ICC 2011. Paris, France, 2011.
  • Çöltekin, A., De Sabbata, S., Willi, C., Vontobel, I., Pfister, S., Kuhn, M., and Lacayo, M. (2011) Modifiable Temporal Unit Problem. Proceedings of the Workshop on Persistent problems in geographic visualization. Paris, France, 2011.
  • De Sabbata, S. (2010) Criteria of Geographic Relevance. Proceedings of the 6th International Conference on Geographic Information Science. Zurich, Switzerland, 2010.
  • De Sabbata, S., and Reichenbacher, T. (2010) A Probabilistic Model of Geographic Relevance. Proceedings of the 6th Workshop on Geographic Information Retrieval. Zurich, Switzerland, 2010.
  • Reichenbacher, T., Crease, P., and De Sabbata, S. (2009) The concept of geographic relevance. Proceedings of the 6th International Symposium on LBS and TeleCartography. Nottingham, UK, 2009.
  • De Sabbata, S., Mizzaro, S., and Vassena, L. (2008) SpaceRank: Using PageRank to estimate location importance. Proceedings of ECAI 2008 Workshop on Mining Social Data, Patras, Greece, 2008.



  • Geographies of Knowledge in Wikipedia

    Geographies of Knowledge in Wikipedia

    Recorded: 15 January 2016 Duration: 00:13:12

    Presentation on Stefano De Sabbata's Wikipedia research, on the occasion of Wikipedia's 15th Birthday.

  • Stefano De Sabbata: The Illustrated Web

    Stefano De Sabbata: The Illustrated Web

    Recorded: 30 March 2014 Duration: 00:09:18

    Stefano De Sabbata shares his visualizations (with Mark Graham) that reveal certain information / behavioral patterns on the Internet which have important political implications.