Qualitative Representation of Change

Current geographic information systems (GISs) have been designed for querying and maintaining static databases representing static phenomena and give little support to those users who wish to represent dynamic information or incorporate temporality into their studies. In order to integrate phenomena that change over space and time in GISs, a better understanding of the underlying components of change and how people reason about change is needed. This paper focuses on a qualitative representation of change. It offers a classification of change based on object identity and the set of operations that either preserve or change identity. These operations can be applied to single or composite objects and combined to express the semantics of sequences of change. An iconic, visual language is developed to represent the various types of change and applied to examples to illustrate the application of this language. Such a formalization of the basic components of change lays the foundation for a new generation of formal models that captures the semantics of change and leads to improved interoperability between GISs and process models or simulation software.