Evaluating the relevance of spatial data in time critical situations

Abstract

Accuracy and relevance are properties that are often mentioned in context with usability and quality of data. The use of GIS and mobile GI services in spatial planning and management requires accurate and relevant data. For usage of spatial data in time critical situations, e. g. disaster management, this is especially true. Decisions must be made in short terms, within hours or minutes. Such situations do not leave any time to evaluate whether the data used for decision making are accurate or relevant. This evaluation has to be done before. The use of inaccurate or irrelevant data, however, can lead to decisions that are inadequate or in the worst case harmful. Increasingly, spatial data are provided via the Internet, and through wireless connections. This is potentially a great chance for GI services in general, but especially for time critical, spatial decision making. An important question that arises is how accuracy and relevance of data can be evaluated, a difficult task taking into account that data come from various sources, are distributed over several servers, and provided by different data producers. Such an evaluation is important because users must have confidence in the data. They must be sure that they use information that is reliable and adequate in a given situation. This requires not only a syntactical control, but especially an understanding of the semantic content of information. The paper pursues these thoughts by investigating methods and techniques to search for specific spatial data sets and simultaneously evaluating the relevance of data. Fitness for use can be examined - to a certain extent - using metadata. But metadata have shortcomings as they describe a fixed number of properties not taking into account adequately data semantics. Ontologies - an approach propagated currently within the framework of the semantic web (Fensel 2004) - are aimed at the identification of relevant data sets. © 2005 Springer-Verlag Berlin Heidelberg.