Evaluation of accuracy of digital map data via multiple comparisons

Abstract

Abstract. Digital map data sets (or geo-databases) are an important part of the spatial data infrastructure (SDI) of the European Community. Different methods of producing large-scale map data are described in the paper, and the aim is to compare the accuracy of these methods. Our analysis is based on statistical tools belonging to the multiple comparisons theory. The first method is the well-known analysis of variance (ANOVA), and the second one is the rank-based method. The latter approach, which is rarely used in geodetic research, allows us to determine the order of the considered methods with respect to the positional accuracy of digital map data that they produce. Using this approach, one can identify the least accurate set of map data or a fragment of a map that should be updated by a new direct survey. The rank-based methods can also be rather easily applied to other technical (engineering) disciplines, e.g. geodesy and cartography.Key words: digital map data, evaluation of positional accuracy, analysis of variance (ANOVA), multiple comparisons, rank-based methods. detic registries of utilities (GESUT database). These data bases were obtained in recent decades using different methods of data acquisition. The INSPIRE directive [1] requires the Commission to establish a geoportal, and the member states of the European Union shall provide access for this geoportal to their infrastructures, as well as to any access points they themselves decide to operate. A release of the INSPIRE geoportal has been published for enhancing access to European spatial data [9]. It enables searching through spatial data sets and spatial data services from the EU member states within the framework of the INSPIRE directive. Evaluation of accuracy of digital map data via multiple comparisonsFurthermore, the European location framework (ELF) BaseMap project [10] provides platforms for accessing INSPIRE-based reference data [11]. This project comprises the datasets provided by national mapping and cadastral authorities (NMCAs) and (in the future) by other data providers [12]. The pilot-phase ELF BaseMap service began in spring 2015 for the Nordic cluster and the Netherlands. Meanwhile, more countries (Denmark, Poland, Czech Republic, and Belgium) have started producing national ELF BaseMap contributions. The recommended production process seems to be feasible, but the map concept needs further revision. In addition, the INSPIRE data models are generally too complex, and not adapted for mapping purposes: overlaps between INSPIRE themes, potential presence of deprecated features, and sometimes attributes of properties are not directly attached to geometry [13].