Spatial data models, or GIS data models, are the ways of representing spatial information in a geographic information system (GIS) database. Because the world is very complex, choices must be made on how to describe objects and phenomena for research and analysis. Typically, the selection of a particular scale of analysis is made, based on information needs dictated by the task at hand, where the level of desired detail is portrayed in the model. Sometimes the choice of scale of analysis is constrained by access to data, particularly where satellite data may offer information only at a particular resolution. The categorization of the objects is also a critical decision: What information is to be included or excluded is carefully considered. From these choices, the spatial ...