Road Networks and Their Incomplete Representation by Network Data Models

Road networks, roads, and junctions are examples of natural language terms whose semantics can be described by affordances of their physical referents. In order to define affordances in such a way that they can be used for classifying and describing instances in a geographic database, one has to deal with the problems of informational incompleteness and limited definability. In this paper, we propose an affordance-based theory of channel networks, based on the work of Hayes [4], as a means to derive necessary conditions for database representations of road networks. By exploring this example, we show that affordance-based logical definitions are a convenient method to capture essential properties of physical objects usually not present in their database representation, but appropriate to explain and define its structure.