I S K O

ISKO STAC working group on Subject Access Metadata

ISKO STAC has set up an international working group to develop a set of guidelines for specifying subject access metadata requirements for procurement of library management systems (LMS). This arises from the observation that such platforms do not typically make effective use of subject metadata or other KOS elements to support search and discovery services. The purpose of the guidelines is to ensure that an LMS enables library users to get maximum value from access metadata such as classification schemes and controlled vocabularies. These represent considerable intellectual effort by cataloguers and indexers but are often overlooked during the procurement process (and sometimes in system design).

Although the recommendations are focusing on federated library search systems, they are relevant in many other information systems, such as archives, museums, for open education resources, for research data etc.

Published works:

The group performed an international survey among academic librarians and analyzes its result. At a later stage of the consultation it will be asking for the views of users, terminology service providers and vendors. If you are interested in participating later on, please contact David Haynes, chair of the working group: david@davidhaynes.co.uk


Subject functionalities of interfaces

KOS-based searching
  1. Searching using KOS concepts, including terms in the form of single or compound words, phrases, pre-coordinated headings, and class captions from classification systems. Although classification systems use notation to represent concepts, a user should not be expected to know and search using these class symbols.
  2. Searching by individual facets or concepts from KOS that compose a complex term (e.g., a class). This includes the ability to search final and complete built classmarks or pre-coordinated index terms, but also individual, built-in facets of the classes or the index terms (cf. Gnoli et al. 2024).
  3. Searching by any combination of individual concepts and facets (as above).
  4. Automatic alignment (translation) of user search terms into KOS terms. If the user writes a synonym not used per se, the system automatically translates it into the preferred term denoting the same concept. The system resorts to the KOS to be able to do that.
  5. Disambiguation—offering the user different concepts (e.g., are you looking for a Jaguar as an animal or a Jaguar as a car?). See, e.g., Google—when typing ‘jaguar,’ it retrieves documents about cars, but on the right, it also offers ‘for animal, see…’.
  6. Linking any index term found in a metadata record to all other metadata records with the same index term. This allows the user to click on the term in the metadata records and directly retrieve all other metadata records with exactly the same term.
  7. Searching by major and minor themes represented by KOS, if supported by the indexing policy
KOS-based browsing
  1. Browsing by concepts from KOS, which is especially useful for those new to the document collection. Hierarchically structured concept schemes, such as hierarchical classification systems or information retrieval thesauri, are most beneficial. At the narrowest hierarchical levels there should be a manageable number of information resources -- perhaps not more than several dozen or so. If there are many more, the structure should be further developed to include more narrower concepts.
  2. Browsing by facets, aspects, and individual concepts from controlled vocabularies, such as individual terms from subject headings, as well as captions and notations representing individual concepts from synthesized classmarks (e.g., in Universal Decimal Classification).
  3. Showing narrower terms and broader terms to the search terms. When the user types a search term, narrower and broader terms should also be shown for them to explore and consider choosing a more specific or a more general term and related terms (Tudhope and Binding 2008). It also helps the user with disambiguation.
  4. Displaying results in systematic order(s). As the function of classification notation is to control the sequential order of concepts (Gnoli 2018), this should also be exploited to present results of a search in a meaningful way, making their examination and selection easier. General subjects will thus precede the more specific ones. The default order of presentation will follow the order in the KOS. However, faceted compounds can also be reordered by privileging a specific facet or interest to the user. Also, as in indexing base themes should have been expressed at the lead of compound classmarks before particular themes, items where the searched concept is the base theme should be presented before those where it is just a particular theme (Gnoli and Cheti 2013).
Enhancing KOS-based indexing
  1. Searching by words from various metadata elements and full-text.
  2. Combining controlled subject searching with searching by other bibliographic fields.
  3. Adding, searching and browsing end-user tags. This allows for end-user perspectives and inclusion of most current terms from the literature.
  4. Linking concepts from one KOS to other relevant ones. This calls for mapping across KOSs in order to support searching across different databases, including multilingual searching.
Image-related functionalities
  1. Searching by image-related characteristics (e.g. size, colour, layout, orientation -- portrait/landscape).
  2. Searching using content-based image retrieval (CBIR) methods (e.g. query by example image).
  3. Searching by features enabled by IIIF (e.g. deep Zoom viewing).
Other search functionalities
  1. Autocompletion, to help the user speed up the typing and help them type accurately.
  2. Autocorrection, to help correct mistypes in order to enhance retrieval.
  3. Highlighting the search term(s) in the retrieved results. This helps the user identify the context of their search term(s).
  4. Searching by Boolean and proximity operators, stemming, truncation, wildcard.
  5. Combining previous search formulations. This supports more complex information needs, such as those of researchers, who may need to combine a number of search terms and syntaxes including Boolean or proximity operators, stemming, truncation, wildcards and similar.
  6. Help on subject searching

(from Golub et al. 2024, § 6)

 

© ISKO 2023 : last updated 2026.01.13