A taxonomy is a way to define and express relationships between things to facilitate organizing, classifying, and discovering relationships in a collection of information. Without a taxonomy, related items must be given arbitrary or ambiguous names when identified. A taxonomy provides a uniform system through a hierarchical or polyarchical structure to show how items are similar or different. Developing a taxonomy involves determining its purpose, scope, relationships to represent, and tools before analyzing content to identify common terms and categories.

1. Taxonomy:
Do I need one?
Leigh White
ElementalSource, LLC

2. Yes

3. What I’ll talk about
• What happens without a taxonomy
• What a taxonomy is and does
• Why a taxonomy is important
• A few first development steps

4. What I won’t talk about
• All the different kinds of taxonomies
• Details about development
• Tools for development
– except DITA subjectScheme (briefly!)

5. A little history

6. What the he** IS that???

7. Oh, let’s call it a…
• Use the native name
• Name it after something familiar
that it’s kind of “like”
• “Like” is murky; you have to define
“like”
– How it looks? Shape? Color? Size?
– How it tastes?
– How it acts?

8. Earth apples, anyone?
• aardappel (Dutch)
• pomme de terre (French)

9. *not apples

10. We know this because
• We have a taxonomy (Linnean
classification) that specifies degrees
of relationship between living things

11. Distant cousins, at best
apple potato
Kingdom Plantae Plantae
Phylum Anthophyta Anthophyta
Class Eudicots Eudicots
Order Rosales Solanales
Family Rosaceae Solanaceae
Genus Malus Solanum
Species M. domestica S. tuberosum

12. So, a taxonomy is
• A way of defining “like”
• A way of expressing relationships
between things
– We might already be instinctively
aware of these relationships but need
to formalize them
• A way of discovering relationships
between things
• An information model

13. Taxonomies are
• typically organized by parent-child
relationships
• typically indicated by the phrase 'is
a kind of' or 'is a subtype of'
• the subtype has the same
properties, behaviors, and
constraints as the supertype plus
one or more additional properties,
behaviors, or constraints

14. Uhh…what?
• For example: car is a kind of
vehicle, so any car is also a vehicle,
but not every vehicle is a car
• The level “car” is more constrained
than the level “vehicle”
• A car has all the properties of a
vehicle plus some other properties
specific to a car

15. Taxonomies are all around us
• It’s our nature to classify
• Many of these taxonomies are
internal, arbitrary and personal
• A true taxonomy must be uniform
and unambiguous

16. Other familiar taxonomies
• Dewey Decimal System
• Library of Congress System
• ICD-9/10 codes
• computer folder system
– probably most common
taxonomy in tech comm

17. And one I especially dig
• A taxonomy of wrongness!
– www.fallacyfiles.org/taxonomy.html

18. We have metadata…why do we need
a taxonomy too?
• Where did that metadata come
from?
– You must have had some idea of how
your content should be classified
– If so, then you already have the
beginnings of a taxonomy, at least in
your head
– So take it a step further

19. Metadata compliments taxonomy
and vice-versa
• Metadata describes an individual piece of
content but doesn’t capture relationships
very well.
• Metadata is part of content so updates
can be unwieldy; better to maintain the
model outside the content
• A taxonomy serves as a roadmap…it both
describes current content and predicts
future content
• A taxonomy highlights similarities (and
differences) across products
• Metadata can pick up where taxonomy
leaves off

20. What else are taxonomies good for?
• Controlled vocabularies
– indexing
– keywords
– glossaries
• Searching/browsing/filtering
– Faceted search
– Filtering for custom doc publishing
• Content reuse

21. Amazon.com

25. So far…
• we’ve looked at hierarchical
taxonomies

26. When hierarchy isn’t enough
 A Cockapoo is a kind of dog. It’s the
product of a poodle and a Cocker
Spaniel. A hierarchy cannot capture
all these relationships.

27. There’s an alternative (polyarchical)

28. Purists might say…
• that you need different notations to
express different kinds of
relationships
• or that you must express the
relationships uniformly

29. Maybe, maybe not
• You need what you need to capture
the relationships you need to
express
• No more, no less - KISS
• The relationships already exist; you
are just using the taxonomy to
express them

30. Decisions to make
• What kind of taxonomy:
– hierarchical, polyarchical, something
else?
• If hierarchical, how many levels?
• If polyarchical, what kinds of
relationships and how designated?
• Tool to use? (meh)
• How to associate content with
taxonomy?

31. Questions to ask
• What will the taxonomy be used for?
– indexing, search, etc.
• Who are the users?
– content creators, clients, SMEs, support, etc.
• What content will the taxonomy cover?
– topics, images, demos, videos, etc.
• What are the scope and limits?
– handling off-topic content—what to
include/exclude
• What are the resources and constraints?
– skills/expertise, timing, technology, funding,
stakeholder roles, etc.

32. More questions to ask
• Who is responsible for development?
• What are secondary/contributor
roles?
• How does taxonomy fit in with other
metadata?
• How to handle ongoing support and
maintenance?

33. Some first steps
• Start small—maybe just one small product
• Do content audit of everything the
taxonomy will categorize
• Compare TOCs of existing deliverables
– Find commonalities, differences
• Compare indexes of existing deliverables
– Discover terms already in use
• Use folder structure

34. More first steps
• Assemble starting list of categories
that cover existing content based on
TOC, index and content audit
• Place existing content within
taxonomy (on paper)
• Create taxonomy task force to
review and refine
– Avoid too many cooks

35. DITA Classification and Subject
Scheme
• Subject scheme
– Defines controlled values (“buckets”)
for classifying content
– Defines relationships between those
buckets
• Classification
– Groups content into appropriate
buckets

36. Subject classification scheme

37. subjectScheme map
<subjectScheme>
<hasInstance>
<subjectdef keys="product">
<subjectdef keys="Widget"/>
<subjectdef keys="module">
<subjectdef keys="Meds"/>
<subjectdef keys="AdminW"/>
</subjectdef>
</subjectdef>
<subjectdef keys="Gadget"/>
<subjectdef keys="module">
<subjectdef keys="AdminG"/>
<subjectdef keys="Labs"/>
</subjectdef>
</subjectdef>
</subjectdef>
</hasInstance>
</subjectScheme>

38. Associate topics with subjects
<map>
<topicref href="t_configure_med.xml">
<topicsubject>
<subjectref keys="Meds"/>
<subjectref keys="AdminW"/>
<subjectref keys="AdminG"/>
</topicsubject>
</topicref>
</map>

39. Recommended reading/viewing
• The Accidental Taxonomist, Heather
Hedden
• Organising Knowledge: Taxonomies,
Knowledge, and Organisational
Effectiveness, Patrick Lambe
• Joe Gelb’s presentation on
subjectScheme:
http://svdig.ditamap.com/videos/sv
dig-2011-05-11.htm

40. Contact me
Leigh White
ElementalSource, LLC
elementalsource@gmail.com
678.467.7706