Integrating Authoritative and Volunteered Geographic Information for spatial planning

This contribution concerns ongoing research by the authors on the integrated use of Social Media Geographic Information (SMGI) and Authoritative Geographic Information (A-GI) as a support in urban and regional planning. Advances in Information and Communication Technologies (ICT) are fostering the production and the sharing of georeferenced user-generated contents, namely Volunteered Geographic Information (VGI) and SMGI, which may complement traditional spatial data sources. VGI is a voluntary contribution by users in order to collect or to disseminate geographic knowledge, while SMGI may be considered a deviation from VGI nature, due to the implicit and passive mode in disseminating geographic information, which is exclusively one embedded attribute of the main shared information. However, SMGI may offer unprecedented opportunities to investigate users’ needs, opinions, behaviors and movements, thus representing a potential support for analysis and decision-making in spatial planning. In this respect, the authors present an original tool called Spatext, which allows collection, management and analysis of SMGI in GIS environment, easing the integration of SMGI with official information. Afterwards, the opportunities for spatial planning arising from SMGI are demonstrated through a case study where this type of information is used for investigating the geography of places. An original methodology is developed applying clustering techniques on the spatial and the temporal components of SMGI collected from Instagram. The applied methodology enables the identification of residential buildings that are not mapped in available official datasets. The results demonstrate how SMGI may be proficiently used to integrate and update A-GI, as well as to investigate the users’ behaviors and movements in an urban environment.