Thesaurus Display and Navigation

1
Session 6

• Thesaurus Display and Navigation

2
Goals of Session 6

• Learn about alphabetical, hierarchical and other
  display types.
• Learn about the UMLS Metathesaurus
• Assess searching and retrieval within and across
  thesauri.
• Exercise Searching vs. browsing in a thesaurus
  retrieval task.
• Discuss Limitations of Web-based thesaurus
  displays.

3
Thesaurus display types

• Alphabetical
• Compare with a back-of-the-book index
• Lists all preferred terms can include
  non-preferred, relationships
• Permuted index
• Hierarchical
• Systematic
• arranges categories or hierarchies of terms
  according to their meanings and logical
  inter-relationships
• ERIC Thesaurus
• Graphic

4
Display style and format

• Font and capitalization
• Bold or all caps for preferred terms
• Italics or lower case for non-preferred terms
• Indentation conventions
• Order of relationships
• (e.g. BT, then NT, then RT), or by facet
• Be consistent

5
Graphic medical thesaurus display?
6
UMLS MetaThesaurus

• Unified Medical Language System
• 2004 Metathesaurus contains
• over 1 million biomedical concepts and 4.3
  million concept names from more than 100
  controlled vocabularies and classifications (many
  in multiple languages)
• Structured by concept, meaning derived from
  position in the hierarchical contexts of various
  source vocabularies
• Who are the users? Is this the best display?

7
Multilingual thesauri

• Separate display for each language.
• ISO 5964 (1985) Guidelines for the establishment
  and development of multilingual thesauri
  (International, 1985a), the equivalent to British
  Standard 6723 1985 (British, 1985a), which
  states clearly right at the start
• The guidelines given in this International
  Standard should be used in conjunction with ISO
  2788, and regarded as an extension of the scope
  of the monolingual guidelines. The majority of
  procedure and recommendations contained in ISO
  2788 are equally valid for a multilingual
  thesaurus.

8
Multilingual thesauri

• Languages are classified broadly into four forms
  
• Inflectional languages, such as Latin, which use
  case - endings. These root-suffixes qualify the
  nouns and verbs.
• Agglutinative languages, such as Turkish, Finnish
  and Hungarian where the root-suffixes can, and
  regularly do, stand as separate words.
• Isolating languages, such as Chinese, which make
  no use of inflection, agglutination or
  prepositions.
• Analytical languages, such as English, which use
  word order, auxiliary words and some vestiges of
  inflection to provide the grammatical structure.

9
Multilingual thesauri

• However, the knowledge of structure is secondary
  to a good working knowledge of the languages
  being handled, including the socio-cultural
  nuances, particularly present in non-scientific
  subjects.

10
Exercise and discussion

• Using the Getty Art and Architecture Thesaurus,
  compare the speed and ease of searching vs.
  browsing for five concepts.
• Discuss Limitations of Web-based thesaurus
  displays.