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How publishers classify their own books

A common complaint by end users is how difficult it is to find books, whether online, or in a print bookshop. A recent presentation by Kat Meyer of the Book Industry Study Group (BISG), a trade association of publishers, revealed how BISG members are concerned about improving book discovery. That seems a perfectly worthwhile goal, so how is BISG going about it?

Ms Meyer stated she was looking to updates in three standards: ONIX, EPUB and  “As these standards are more widely adopted, many of the problems publishers currently face around book discovery and user experience will be resolved” stated one commentator.

The first of these is ONIX. But the standard Ms Meyer is recommending, ONIX 3.0, was introduced in 2009, all of six years ago. “Anything that can help describe or draw attention to your book is captured on ONIX”, explained Meyer. One could argue that a standard that has still not been widely adopted in six years after its introduction is in some way flawed (but that’s something for another post).

Every book ONIX file contains a BISG initiative, the official book industry subject classification. This is known as the BISAC subject headings, and is revised annually. In fact the 2015 edition, according to Ms Meyer, contains more than 500 new codes. That’s right, more than 500 codes added in 2015 alone!  That’s a lot of codes. How many subject codes are there in the BISAC subject headings overall?  From the BISAC home page, there are 52 top-level catgories (variously stated as 52 or 54 on the BISG tutorial page), such as “art”, “poetry”, “photography”, “reference”. Within each top-level category there are second-level subjects. Thus, within “architecture” there is “architecture/history/general”. Architecture has 39 second-tier categories of this kind.  In fact there can be up to four levels of hierarchy, such as “HISTORY / Africa / South / Republic of South Africa”.

Now, BISG recommends adding a maximum of three subject headings, and that they should be placed in order of priority. This means that those allocating BISAC codes have to take a decision about the primary location under which this title will appear. This is a real challenge – in fact, with thousands of subject headings to choose from, the publisher will have difficulty knowing they have selected the right one. BISG recommends using machine-based tools to search on the entire list of BISAC subject codes In other words the list of subjects is so long they recommend using a machine to identify what codes exist. Is it possible some of these codes may be similar! Absolutely! As the tutorial states:


similar subjects appear in different sections to reflect different ways of approaching the topic (e.g., "HEALTH & FITNESS / Sexuality", "PSYCHOLOGY / Human Sexuality", "RELIGION / Sexuality & Gender Studies", "SELF-HELP / Sexual Instruction", not to mention related subjects under JUVENILE FICTION, JUVENILE NONFICTION, YOUNG ADULT FICTION, YOUNG ADULT NONFICTION, and SOCIAL SCIENCE).


With such fine distinctions, it will be a difficult task to pick one primary code. For example, in the section mind, body and spirit, cataloguers are expected to be able to distinguish an “out-of-body experience” from a “near-death experience”, and to distinguish “UFOs” from “Unexplained phenomena”. If you have to select just one primary category from that lot, it is not surprising books are not easily found.

It might be helpful to know what the avavilable BISAC headings are. Unless you are a member of BISG, you aren’t actually allowed to download it. You might think that BISG had a vested interest in everyone knowing what the subject headings are, but it appears not, from the wording on the BISAC site.

If you think that it might be useful to see what BISAC codes other publishers have used for a similar book, think again! “There is no single source for determining what BISAC heading has been assigned to a published or forthcoming book.” In fact, BISG recommend “that the nine-character code not appear on the book or in catalogs”.

How widely are the full BISAC headings used? To test the system out, I looked on Amazon books for “near-death experiences”. I got over 75 pages of hits, including, on the first page,  The Near Death Experience: Thaddeus Murfee Legal Thriller Series Books 10. So was this categorised by BISAC as first of all fiction, or first of all near-death experience? Amazon had no problem retrieving it. 

In any case, Amazon’s own classification system seems to be different to that of BISAC. Amazon has “Mind, Body & Spirit / Thought and Practice / Reincarnation”. BISAC has “Body, Mind & Spirit / Afterlife & Reincarnation”. If the world’s largest book retailer is using a different classification, then what hope for BISAC codes?

All in all, the BISAC headings appear to be over-complex, difficult to add, and hence difficult to find, and it is difficult to see that they are being used extensively as intended. Next time I search for “near-death experience”, I’ll trust to Google – or to Amazon.