Links: Curation

It has been noted  that changes to scientific data archives are accretive – most changes are additive – although deletion and modification also occur. Scientific data is typically structured hierarchically, allowing a hierarchical key structure to be exploited in archiving changes to the data. Managing versions of a data resource can be performed on the basis of diffs (i.e. by recording the editing steps that cause the change). However, there are advantages for an approach where all objects have an associated timestamp. The central notions of hierarchical organisation, objects and timestamps (Buneman, Fan et al. 2001, 2002) also apply to ontologies and ontology management, and this is the approach we plan to adopt. Given the problems noted by Noy et al. (2003) with the simple diff approach, our approach will also be structure-based. We shall identify types of ontological changes that occur in practice, taking the procedures used in practice, e.g. by the Gene Ontology, as a starting point. As we do not assume that ontologies will make use of formalisms such as Description Logic, our approach is not reliant on the widespread uptake of this particular logic. However, we will exploit any formalism that is associated with an ontology, which may be DL or first-order logic.