1. MedicalcnIformatisGroup i Indexes, Topic maps & the semantic net Dr Jeremy Rogers MRCGP Clinical Research Fellow Medical Informatics Group University of Manchester

2. MedicalcnIformatisGroup i Outline What’s an Index ? What’s a Topic Map ? Uses Strengths & Weaknesses

3. MedicalcnIformatisGroup i What’s in an index ? La Bohème, 10, 70, 197-198, 326 Cavalleria Rusticana, 71, 203-204 The Girl of the Golden West, see La fanciulla del West Leoncavallo, Ruggiero I Pagliacci, 71-72, 122, 247-249, 326 Madama Butterfly, 70-71, 234-236, 326 Manon Lescaut, 294 Mascagni, Pietro Cavalleria Rusticana, 71, 203-204 Puccini, Giacomo, 69-71 La Bohème, 10, 70, 197-198, 326 La fanciulla del West, 291 Madama Butterfly, 70-71, 234-236, 326 Manon Lescaut, 294 Tosca, 26, 70, 274-276, 326 Turandot, 70, 282-284, 326 Rustic Chivalry, see Cavalleria Rusticana singers, 39-52, See also individual names baritone, 46 bass, 46-47 soprano, 41-42, 337 tenor, 44-45 soprano, 41-42, 337 tenors, 44-45 Tosca, 26, 70, 274-276, 326 Turandot, 70, 282-284, 326 different types of topic (the names of operas are shown in italic ) different types of occurrence (references to synopses are in bold ) synonyms for the same topic links to associated topics ( see also ) associations between different topics (e.g. between a composer and his works) supertype and subtype information

4. MedicalcnIformatisGroup i What’s a topic map ? Very similar to an index except… Implicit information made explicit –Not represented in typographical conventions Consistent use of topics within indexes –Consistent use between indexes ?

5. MedicalcnIformatisGroup i What is a topic map ? What is a topic map ? www.topicmaps.org http://www.ontopia.net/topicmaps/materials/tao.html Means to convey knowledge about resources –Knowledge embodied in a superimposed layer –A ‘map’ of the resources Captures –the subjects of which resources speak –the relationships between those subjects –implementation-independent

6. MedicalcnIformatisGroup i What is a Topic Map ? The central concepts in topic maps are: Occurrences e.,g. a physical book, a web page = the page numbers Associations e.g. ‘is-author-of’ = ‘see also’ links Topics e.g. ‘Shakespeare’, ‘Hamlet’ = the list of subjects in an index

7. MedicalcnIformatisGroup i History of Topic Maps 1993 first description of topic maps 2000 ISO/IEC standard 13250:2000 –Used HyTM 2001 minor update –To include XTM Main protagonists today –(a small but active community) –Ontopia (Oslo) –Techuila (Oxford) –InfoLoom (New York) –TopicMaps.Org

8. MedicalcnIformatisGroup i An example: SubjectsType Shakespeare 1 Hamlet 2 Jonson 3 London 4 Stratford 5 Volpone 6 Play 7 Town 8 Associations Person 9 Topics

9. An Example in XTM: Shakespeare 1 Hamlet 2 Play 7 writtenBy author work Hamlet, Prince of Denmark The Scottish Play Hamlet, Prince of Denmark The Scottish Play Hamlet, Prince of Denmark The Scottish Play Hamlet, Prince of Denmark The Scottish Play Hamlet, Prince of Denmark The Scottish Play Hamlet, Prince of Denmark The Scottish Play Hamlet, Prince of Denmark The Scottish Play

10. MedicalcnIformatisGroup i Demo: Ontopedia

11. MedicalcnIformatisGroup i What are they for ? Indexing large resources you can’t write in directly –Original ‘back of book index’ motivation Organising web sites –Some elements on a web page generated from topic map E.g. www.ontopia.net/operamap/ Expert systems Way of storing information flows & audit trails –Or any other network of info, really

12. MedicalcnIformatisGroup i How do I make one ? By hand –Very labour intensive, but usually highest quality –Some tools e.g. Ontopia, TMTab for Protégé, TMDesigner Semi-automagically –If the original data is already well structured –Some language processing tools can help Automatic Transformation –Re-write other sources of the same information Useful websites –www.ontopia.net –www.techquila.com

13. MedicalcnIformatisGroup i Strengths of Topic Maps… Good for large or dynamic information sources –E.g. ‘2001 Tax Products’ CDROM from US IRS –E.g. www.quid.fr Better querying than a static index –‘Find all composers who have written an opera that was not first performed in Italy but was based on a work originally written by Shakespeare’ Making it possible/easier to merge knowledge resources –allegedly

14. MedicalcnIformatisGroup i …and limitations Not so good for very large information sources –E.g. The entire world wide web (= ‘The Semantic Web’) –The ontology problem Different topics used differently at different times & by different authors No inferencing (yet) –E.g. IF Aria sung-in Act I AND Act I part-of Tosca THEN Aria sung-in Tosca Limitations in what can be said –E.g. Child must have exactly one mother –E.g. Mother of a baby kangaroo must also be a kangaroo

15. MedicalcnIformatisGroup i Current Developments Standardising the query language –ISO/IEC 18048 TMQL Standardising the constraint language –ISO/IEC 19756 TMCL (based on OWL ?) “All persons must be born somewhere” “A person may have died somewhere” Experiments with inferencing

16. MedicalcnIformatisGroup i Topic maps vs. semantic nets A Semantic Net is any data structure network with nodes representing objects, classes or concepts, and the arcs representing relations between them (e.g. is-a, part-of etc) Therefore, all topic maps are a kind of semantic net But not all semantic nets are topic maps –Because richer semantic nets may include e.g. cardinality –Not all semantic nets need external references Other kinds of semantic nets: –Mind maps –Entity Relation Diagrams & UML (databases) –Description Logics (ontologies)

17. MedicalcnIformatisGroup i Summary Topic Maps formalise back of book indexing –Especially useful for electronic age –Makes the index machine-readable Aspirations for more –Usual plans for global domination Relatively young –Details still being finalised –Low uptake so far –But key exemplars