On the integration of object-based models and field-based models in GIS

This paper proposes a common base-model for the classical object-based and field-based conceptual models in GIS. The model, which is called the PGOModel or 'Parameterized Geographic Object Model', is given a formal definition by using the UML modelling language. Within the scope of the paper, it has been shown that the PGOModel encompasses the classical object-based and field-based models. Two extensive examples demonstrate the application of the PGO model. The PGOModel seems ontologically well founded, except for the so-called PGOAtom concept.