Introducing Topic Maps

Patrick DurusauConvener, Topic Maps Working Group, ISO

Overview

The original use case Defining some termsAdding indexes = trouble!Rules for InterchangeDoes change happen?Do your subjects matter?Are topic maps hard?Example topic maps

The original use case

Multi-volume series, independent indexesPublisher – reusing series as documentation for software means salesVendors – reusing series means not writing documentationWin-Win? Unfortunately, no.The reason why is the story of topic maps.

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. :-(

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.

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)

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)

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)

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

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?”

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.

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).

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

Rules for Interchange IV

Writing a topic map requires syntax (Yikes!)Verbose way: XTM (XML Topic Maps) Requires XML authoring software/skillsCTM – Compact Topic Maps Syntax ASCII format that is brief and “relatively” easy to learnIf not authoring topic maps with an application, strongly suggest CTM

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.

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

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?

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)

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.

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?

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.

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.

Bonus slide

Topic Maps Lab: http://www.topicmapslab.de/

(EU funded research project) Topic Maps Standards:

http://www.isotopicmaps.org