Introducing Topic Maps

1. Patrick Durusau Convener, Topic Maps Working Group, ISO Introducing Topic Maps

2. Overview • The original use case • Defining some terms • Adding indexes = trouble! • Rules for Interchange • Does change happen? • Do your subjects matter? • Are topic maps hard? • Example topic maps

3. The original use case • Multi-volume series, independent indexes • Publisher – reusing series as documentation for software means sales • Vendors – reusing series means not writing documentation • Win-Win? • Unfortunately, no. • The reason why is the story of topic maps.

4. The original use case II • Files in markup (cutting edge for the time)‏ • Professional publisher/authors • Professional software vendors • So, where's the beef? • Arrrgh! The publisher, authors, indexers and vendors, all used different vocabularies for the same things. :-(

5. The original use case III • Mapping between the documentation and any vendor would be one off, a term at a time. • Literally thousands of terms, spread across thousands of pages, simply not doable. • Project split into parts that matured into DocBook (a markup format for technical literature) and Topic Maps.

6. Defining some terms • An example from an index: • Sorting, 242. see also ....xsl:sort • collations and, 106, 459 • distinct value, Xquery and, 750 • Topics = sorting, collations, distinct value, Xquery – (things to talk about)‏ • Occurrences = where to find more information (here page numbers)‏ • Associations = collations and sorting is one (note, we don't know the nature of that association, just that it exists.)‏ • Well, put like that, topic maps aren't so unfamiliar. ;-) (but there's more)‏

7. Defining some terms II • Let's try another index: • Sorting • flexible • flexible sort orders, 409 • flexible sort values, 412 • Overview, 409 • OK, topics are flexible sort orders, flexible sort values, occurrences are the page numbers, some implied association between flexible and sorting. Gee, this isn't so hard! (see next slide)‏

8. Adding indexes = trouble! • Let's take our two indexes and “merge” them: • Sorting, 242. see also ....xsl:sort • collations and, 106, 459 • distinct value, Xquery and, 750 • flexible • flexible sort orders, 409 • flexible sort values, 412 • Overview, 409 • As Ben Stein (http://en.wikipedia.org/wiki/Ben_Stein) would say: “wow.” (use imagination)‏

9. Adding indexes = trouble! II • Not only ugly but useless • Occurrences (page numbers) no long tied to a particular book • Subjects aren't identified, as least in an interchangeable way • Associations remain implied • Need to solve several problems at once

10. Adding indexes = trouble! III • Problems to solve: • Identify subjects (not by ad hoc strings)‏ • Bind subjects to occurrences of those subjects • Explicitly represent associations between subjects • Do all that in a way that supports blind interchange • Can you say “topic maps?”

11. Rule for interchange • Rules enable interchange • Topic maps call sets of those rules “legends” • Legends define what is shown by a map and how to read it • The only standardized topic maps legend is the Topic Maps Data Model (TMDM). • TMDM = Rules of the topic maps road.

12. Rules for interchange II • First problem: How to share identification of a subject? • Recall that my name and your name for a subject may be different, or change over time. (not to mention simply using a name may not be enough)‏ • TMDM solution is to provide all subjects with addresses on the World Wide Web (sorta).

13. Rules for Interchange III • TMDM divides subjects into two large classes • Subjects located at World Wide Web addresses (my website for example)‏ • Subjects given a World Wide Web address where you can find a description of that subject (Ben Stein's wiki page for example)‏ • Computers use the addresses for merging purposes, the content aids human users in judging if they mean the same subject

14. Rules for Interchange IV • Writing a topic map requires syntax (Yikes!)‏ • Verbose way: XTM (XML Topic Maps) • Requires XML authoring software/skills • CTM – Compact Topic Maps Syntax • ASCII format that is brief and “relatively” easy to learn • If not authoring topic maps with an application, strongly suggest CTM

15. Does change happen? • Is that a silly question? • Check your local OPAC • Can I search it using terms I learned 20 or more years ago? Terms that are no longer in use? • BTW, see Sanford Berman, Prejudices and Antipathies: A Tract on the LC Subject Heads Concerning People, for one view.

16. Does change happen? II • Losing change means • Loss of historical context for texts/authors • Loss of access to previously cataloged material • Loss of potential mapping from old terminology to new terminology • Loss of the ability to retrieve all the information on a given subject

17. Do your subjects matter? • Mapping historic change is a very large mountain • Eeyore types saying: Best not even to try • For the universe of information at large, perhaps their right • But what about subjects that matter to us now? What about mapping those subjects?

18. Do your subjects matter? II • Well, ... the conversation begins... • ...we don't have a field, table, category, ontological class, etc. for your subject, sorry... • ...we can't modify X system just because someone wants to say something different... • So, what we can say is a function of our technology? (seems wrong-headed)‏

19. Do your subjects matter? III • Err, did I mention that any subject can be represented by a topic? • Ok, so that means that the record returned in a web interface can be a subject? Yes? • So that means I could associate other information with that “subject”? Yes? • If you can “see” it, you can “map” it.

20. Do your subjects matter? IV • Topic maps need not replace existing systems but can supplement them • May not have minority language qualified librarians on staff but may have minority communities • Can't offer “write” access to the catalog but what about “supplementing” the catalog?

21. Are topic maps hard? • Honest answer: Depends. ;-)‏ • More useful answer: How imaginative vs. disciplined are you? • Can talk about an unbounded number of subjects, easy to get lost. • Authoring a “useful” topic map depends on your imaging subjects to represent but having the discipline to choose the “right” ones.

22. Example topic maps • Highwire Press • Musica Migrans • New Zealand Electronic Text Centre • Topic maps are also in use by such diverse groups as the Internal Revenue Service (US), the German and Norwegian post offices, the Norwegian stock exchange (ISO 9000 conformance) and others.

23. Bonus slide • Topic Maps Lab: http://www.topicmapslab.de/ • (EU funded research project)‏ • Topic Maps Standards: http://www.isotopicmaps.org