Linking thesauri: ELSST as a hub for social science data terms

Without controlled index terms, data retrieval within a data catalogue becomes at best hit and miss. The UK Data Archive manages two thesauri: the multilingual ELSST thesaurus, and the monolingual HASSET thesaurus, from which it is derived. Over the last year, through funding from the UK's ESRC, the Archive has developed both of these thesauri, plus their management applications, and created linkages between them. Extending ISO 25964, the UKDA has developed a way of mapping its social science thesauri to facilitate cross-national data retrieval. It has also created SKOS formats and is developing a new and innovative application for thesaurus management which combines term visualisation with tree structures. The two thesauri now share a clearly defined, common set of core concepts, but have room for divergence. The new application will allow terms to be promoted to the core set, where they exhibit partial or exact equivalence, or be demoted to 'non-core'. The application allows authorised language equivalents to be added to ELSST terms. Bundled suggestions will also be made for changes to the thesaurus terms or structure, linked to the tree structure. This paper describes the new application and the processes used within the UKDA for thesaurus management.