Implementing Anchoring

In an earlier paper we introduced Anchoring, a new approach for handling indeterminate location in a spatial information system. Here we develop it further, showing how Anchoring can be made to work in real systems. In particular, we specify a new kind of locational component for a spatial data model. We then show how that component can be implemented into an object-relational database with extensions conforming to the OpenGIS Consortium's Simple Feature Model. We argue that Anchoring, in contrast to other formalisms for handling indeterminate location, is better suited to the needs of a spatial data provider who, in supplying data to different organisations, needs to be authoritative, and thus does not want to compromise data quality by representing indeterminate data with unwarranted precision. Anchoring, in providing new ways to describe spatiality, allows that we state only what we know for certain.