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Positional and shape quality of areal entities in geographic databases: quality information aggregation versus measures classification / Atef Bel Hadj Ali (2001) 

Public Titre : Positional and shape quality of areal entities in geographic databases: quality information aggregation versus measures classification Type de document : Article/Communication Auteurs : Atef Bel Hadj Ali , Auteur Editeur : Toulouse : Université de Toulouse 3 Paul Sabatier Année de publication : 2001 Conférence : ECSQARU 2001, 6th European conference on symbolic and quantitative approaches to reasoning with uncertainty, workshop Spatio-Temporal Reasoning and Geographic Information Systems 18/09/2001 18/09/2001 Toulouse France Proceedings Springer Importance : 16 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées [Termes IGN] appariement automatique [Termes IGN] classification automatique [Termes IGN] classification non dirigée [Termes IGN] données multisources [Termes IGN] erreur [Termes IGN] qualité des données [Termes IGN] système d'information géographique Résumé : (auteur) The production of geographic information is a complex process that can not be considered as deterministic because several digitisations of the same area with the same specifications and the same sources produce different data. Errors in geographical databases can not be avoided. They result from each production step of geographical information and are mainly due to the limited accuracy of capture devices and possible human limits during data interpretation of areal photographs. Small errors may be unimportant for the use of GIS but the quick development of geoinformation raises new problems. Being able to use data coming from different sources is one of these problems: e.g. users must be able to simultaneously use topographic data together with cartographic data or with their own data. To achieve this task, the use of geographical data requires the supply of metadata. This paper presents a methodology for assessing shape and positional quality of areal entities (polygons), and how to present this quality information depending on applications. This methodology is based on the measurement of discrepancies between two datasets. In this context, matching data sets is required. An algorithm for matching data sets is a briefly presented, with a focus on its capability to decide in a dynamic way the correctness of multiple matching links established between areal entities. This paper deals also, with some representations and metrics that account for the specificity of areal entities and allow to easily grasp how these entities are structured. Areal entities are various. Metrics detailed in this paper allow for the measurement of discrepancies between shape and position of matched entities. It has been proven that the use of only one measure does not enable to correctly assess geometrical quality, because each measure provides information that an-other do not. However, it is necessary to combine all these measures between them to achieve a correct assessment. The last part of this paper presents techniques used to combine measures. Those techniques consist in a classification of matched entities versus measures. This classification is performed in order to discriminate classes that have the similar shape and positional quality. At each level of classification, decision rules are generated and provide the user with indications about the quality of its data. The aggregation of the data quality information is made according to these levels of classification. To illustrate this methodology for quality assessment and aggregation of areal geographic entities, a prototype is finally presented. Numéro de notice : C2001-056 Affiliation des auteurs : COGIT (1988-2011) Thématique : GEOMATIQUE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98546

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