Tag Archives: classification

Three resources for learning Dewey Decimal Classification

So I’m halfway through the classification part of my Cataloguing & Classification module. After three weeks of theory, last week we finally got stuck into Dewey. And what a week it has been! After a somewhat leisurely start to the term, the workload went up exponentially. But that’s OK, because it’s all fascinating stuff.

I should mention at this point that the module is not so much about professional training in classification. Rather, we are learning the underlying principles of classification schemes such as Dewey and UDC so that we can evaluate their suitability for organising collections. And with only one week dedicated to each of the two classification schemes in the syllabus, anything beyond this would be pretty much impossible. But even so, part of the coursework will be to classify a number of documents.

In any case, last week provided ample opportunity to practice Dewey. Our lecturer has made a workbook available, which was challenging but rewarding. I’m sure it will be no different for UDC. I really enjoy classification, so I was on the search for more opportunities to practice and to learn more about Dewey. Here are my top 3 resources:

1. Vanda Broughton’s textbook on classification

BROUGHTON, V., 2004, Essential classification. London: Facet Publishing

This textbook is quickly becoming my classification bible. Not only was it immensely helpful when you want to brush up on anything from aspect classification to vocabulary control, it also had chapters dedicated to the Library of Congress Classification, Dewey Decimal Classification, and Universal Decimal Classification. They each come with a number of exercises, and I slowly worked my way through the Dewey chapter last week. Most importantly, the answers are given at the back!

2. The Dewey Blog

025.431: The Dewey Blog (http://ddc.typepad.com/).

This blog is pretty awesome! The tagline is “Everything you always wanted to know about the Dewey Decimal Classification System but were afraid to ask…” and this describes the theme of the blog rather well. My favourites are the posts that talk you through how you would classify documents on news topics, e.g. the mission of the Rosetta spacecraft to Comet 67P Churyumov-Gerasimenko.

3. Dewey Training Courses on the OCLC website


Most of these seem to consist of PowerPoint slides and associated exercises. So far, I have only worked my way through the material and exercises on Table 1 (standard subdivisions). I liked that there are lots of examples on how you arrive at a given classmark.

And as a bonus…

Question: How many librarians does it take to change a lightbulb?
Answer: 645.5 *

(via INALJ)

* 645.5: Lighting fixtures (Dewey Decimal Classification)


A whole new world… of classification vocabulary

I’m now well into the cataloguing and classification module, which I have been looking forward to ever since I enrolled on the MSc. So far, I have not been disappointed.

We’re in week 3, and already have learnt a lot about the basics of bibliographic classification, with examples from a range of classification schemes. From next week onwards, we’ll have a closer look at two particular classification schemes – Dewey Decimal and UDC.

It is fair to say that there have been many new terms since the module started:

word cloud of classification vocabulary

Here are some of terms explained, mainly for my own benefit:

citation order: this refers to the subject heading or classmark, more specifically to the order in which the different concepts that make up a subject are combined in the classmark. We’re mainly talking about faceted classification schemes here.

compound subject: a subject which consists of more than one concept. The concepts cannot be separated without changing the meaning of the subject. Examples: financial management; electrical engineering.

semantic relationships: they are “hierarchical relationships proper” (Broughton, 2004, p. 25) – relationships between concepts based on hierarchy and independent of context. For example, a bonobo will always be a great ape or Hominidae (well, unless biologists decide to change the scientific classification, but you know what I mean), and a finger will always be part of a hand. Want to know more? The “bonobo – great ape” relationship is an example of a thing-kind relationship (“a bonobo is a kind of great ape”) and the “finger – hand relationship” is an example of a whole-part relationship (“a finger is part of the hand”). Thirdly, we can also have instance relationships, e.g. the Thames is an instance of a river.

The following terms all tell you something about a given classification scheme:

literary warrant: how well does the classification scheme take into account and match the published literature in a field? For example, if the bulk of textbooks published on, say, learning Hebrew as a foreign language falls into the four areas grammar, vocabulary, listening, and reading, can we find these four concepts in the classification scheme?

user warrant: how well does the classification scheme take into account the expectations of users?

exhaustivity: in terms of indexing, how well does the classification scheme allow the indexer to represent all the different elements of a subject in the subject heading or classmark? Coming from a slightly different angle, Rowley and Hartley (2008, p. 131f.) describe this concept very well in relation to different information retrieval systems: at the basic level we have summarisation (e.g. a subject heading), then the most significant subjects (e.g. chapter headings), then detailed subject specification (e.g. a back-of-book index), and finally the full text – “the ultimate level of exhaustivity”.

specificity: how well does the classification scheme allow you to classify a document at the right level? For example, if you want to classify a monograph on the Reformation in Germany, and your schedule for German History goes like the (very quick and dirty) one below, you will end up having to classify the monograph under Modern History, which is not very specific!

AA History of Germany
      AAA Prehistoric
      AAB Germanic
      AAC Medieval
      AAD Modern

You would be better of if the schedule was more like this (also very quick and dirty):

AA History of Germany
      AAA Prehistoric
      AAB Roman
      AAC Medieval
      AAD Early Modern
            AADA Renaissance
            AADB Reformation
      AAE Modern

flexibility: how much choice does the classification scheme offer to the classifier, e.g. can you change the citation order, or are there alternative locations for a subject? If so, once you have made up your mind as to what to do, stick with that decision.

hospitality: how well is the classification scheme able to accommodate new subjects (e.g. Web 2.0). For example, are there gaps in the notation where you could slot in new subjects?


BROUGHTON, V., 2004. Essential Classification. London: Facet Publishing.

ROWLEY, J. and HARTLEY, R., 2008. Organizing Knowledge. An Introduction to Managing Acess to Information. 4th ed. Farnham: Ashgate.

Hello, new term!

The spring term starts on Monday and I cannot wait. My note-taking pencil is sharpened, books have been taken out from the library, and I have created a new folder for each module on my computer. The excitement is palpable.

I am massively excited about the new term not just because I still love being a student again, but also because I will get to study Cataloguing & Classification alongside Knowledge Organisation. Some of my favourite things! I did  the Coursera Metadata MOOC run by Jeffery Pomerantz from the University of North Carolina at Chapel Hill last summer and ever since, I have been hooked. Although the MOOC was mainly about metadata (the name is a giveaway…), we touched upon related topics a lot: Library of Congress Subject Headings, Dewey Decimal Classification, ontologies and thesauri… I cannot wait to learn more about to all of this.

And I cannot wait to read these babies:

cataloguing and classification books