Adopting a Constructivist Grounded Theory Method, this thesis conducted in-depth interviews with 57 purposefully selected participants, comprised of practising librarians, researchers, metadata consultants and library users. The interview data was analysed using three stages of iterative data analysis: open coding, focused coding and theoretical coding. The analysis resulted in the emergence of four Core Categories, namely, metadata Enriching, Linking, Openness and Filtering. Further integration of the Core Categories resulted in the emergence of a theory of digital library metadata; The Theory of Metadata Enriching and Filtering.
The theory stipulates that metadata that has been enriched, by melding standards-based (a priori) and socially-constructed (post-hoc) metadata, cannot be optimally utilised unless the resulting metadata is contextually and semantically linked to both internal and external information sources. Moreover, in order to exploit the full benefits of such linking, metadata must be made openly accessible, where it can be shared, re-used, mixed and matched, thus reducing metadata duplication. Ultimately, metadata that has been enriched (by linking and being made openly accessible) should be filtered for each user, via a flexible, personalised, and re-configurable interface.
The theory provides a holistic framework demonstrating the interdependence between expert curated and socially-constructed metadata, wherein the former helps to structure the latter, whilst the latter provides diversity to the former. This theory also suggests a conceptual shift from the current metadata principle of sufficiency and necessity, which has resulted in metadata simplicity, to the principle of metadata enriching where information objects are described using a multiplicity of users’ perspectives (interpretations). Central to this theory is the consideration of users as pro-active metadata creators rather than mere consumers, whilst librarians are creators of a priori metadata and experts at providing structure, granularity, and interoperability to post-hoc metadata. The theory elegantly delineates metadata functions into two: enriching (metadata content) and filtering (interface). By providing underlying principles, this theory should enable standards-agencies, librarians, and systems developers to better address the changing needs of users as well as to adapt themselves to recent technological advances.