Assessing OSM Road Positional Quality With Authoritative Data

Online collaborative mapping projects, such as OpenStreetMap (OSM), have been developed not only to provide public and free information about many types of geospatial features, including communication and transportation networks such as roads, trails and railways, but also to give its users the chance to contribute with their local knowledge about the places. There must be, however, a special concern for the quality assurance within these community driven maps. The aim of this paper is to assess the positional differences between the road network available in OSM for some regions of the Coimbra Municipality, Portugal, and the data provided by the Coimbra City Hall, considered as reference. The assessment is made by computing the distance between the features’ lines, extracted from OSM and the reference data, using two approaches. One regards the application of a workflow, which uses tools already available in GIS software. The other approach applies directly the FOSS4G-based procedure developed by Brovelli et al. (2015).