How much information is geospatially referenced? Networks and cognition

This paper presents two approaches that aim to capture the portion of geospatially referenced information in user-generated content: a network approach and a cognitive approach. The German Wikipedia is used as research corpus, which is considered a network with the articles being nodes and the links being edges. The Network Degree of Geospatial Reference (NDGR) is introduced as a measurement unit for the network approach. We define NDGR as the shortest path between any Wikipedia article and the closest article within the network that is labeled with coordinates in its headline. Results of an analysis of the German Wikipedia employing this approach are reported. The cognitive approach is manifested by the Categories of Geospatial Reference (CGR): Direct, Indirect and Non-Geospatial Reference. These are categories that may be distinguished and applied by humans. An empirical study including 380 participants was conducted. The results of both approaches are synthesized with the aim to (1) examine correlations between NDGR and the human conceptualization of geospatial reference and (2) to separate geospatial from non-geospatial information. This provides empirical evidence to (in)validate the much-quoted assertion that 80% of all information is geospatially referenced.