Τα Γεωγραφικά συστήματα πληροφοριών στα χέρια εθελοντών. Το παράδειγμα του OpenStreetMap στο Λονδίνο και την Αθήνα

The technological developments have contributed to the increase of the online
mapping. One representative example is OpenStreetMap (OSM) which was launched in 2003 and was spread all over the world in relatively short time. However, its differentiation from the conventional maps made it unique among the other competitive geographic information systems. The differentiation is based on the volunteers who are free to collect, edit and use the spatial data. A whole philosophy has been developed beyond the specific phenomenon named Neogeography and the Geographic Information which is based on amateurs’ work is called Volunteered. It is obvious that the advantages are really attractive especially if it is taken into consideration that OSM is free of charge and other copyright restrictions. However, the query that is posed concerns the quality of the data. The aim of the study is to focus on comparative research between the neogeographic datasets and the conventional datasets studying the quality of the OSM data over the positional accuracy and the length completeness. The study concerns the wider area of Athens and London and the main objective is to figure out the applications for which the OSM is appropriate. According to the research, the OSM is at comparable levels to the conventional Geographic Information Systems and it can be used in a variety of applications. Its power is based on the volunteers who amend and improve the data. A new era has begun in Cartography due to the Volunteered Geographic Information.