Thesaurus vs taxonomy vs subject headings

A few weeks ago, I attended a course on how to build a thesaurus (opens in new window). Having thought about it a fair bit since the course, I’ve come to the conclusion that what we probably want to do here, at least in the short term, is not to create a thesaurus but to put together a list of subject terms. Here’s my thinking…

A thesaurus is a comprehensive listing of all the possible terms that someone might use to describe content within our subject (not an official definition but it’ll do for my purposes here). Although this means that whatever term someone might use, the thesaurus should make sure that they use the same one as the cataloguer, the problem is in the time required to create one. One of the things that I picked up from my course is that building a thesaurus from scratch is a very large task. Having discovered that there isn’t anything quite right out there already, I think I’d be looking at quite a bit of work. Also, although it is more flexible, I need to use more terms to describe the subject. Where a single subject heading will capture it, I might need to use several terms from the thesaurus.

A taxonomy has the same description limitation as the thesaurus (potentially many terms required) but is much quicker to produce. Of course, a user needs to guess the right term where a thesaurus will direct them to it, providing they’ve had a reasonably good guess in the first place.

Subject headings are a little less quick to produce than a taxonomy but still a quicker process than a thesaurus and they can describe the subject a little more effectively (this is because they provide context which an isolated word does not possess). Subject headings have their own pitfalls, of course, particularly when it comes to consistency of use over time.

So here is how I sort of see things looking:

(I don't know what's going on with this table...scroll down...it's there...I will look into it later as I must get going now!)

	Taxonomy	Thesaurus	Subject headings
Time to create	Fast	Slow	Medium
Versatility	High	High	Low
Ease of use	Low	High	Medium
Ease of Maintenance	High	Low	Low
Structure	Low	High	Medium

The time to create is an initial outlay of resource and is not ongoing. As a result, from a long-term perspective, the fact that this might be Slow isn’t too critical. The bit that makes a thesaurus less attractive as an option is the effort required to maintain it (of course there is software available to assist). The appeal to me of the subject headings is their time to create and their relative ease of use. I think that I would start the subject heading creation process by building a taxonomy and use that to develop the subjects. After creating and introducing subject headings initially, I think that I should use that same taxonomy (and the finished subject headings) to develop a thesaurus and aim to use that in the longer-term.

What do you think? Are there flaws in my thinking here? Are there other aspects that I should consider? This hasn’t exactly been a scientific process so there is every chance that I have missed something…

So, was the course a waste of time/money? Not at all. I couldn’t have arrived at a conclusion around the best way forward for my organisation without having attended it, even though the conclusion was to not build a thesaurus. Also, if/when we do get to the point where we want to introduce a thesaurus, I will have an idea as to where to start.