The Zombie Stack Exchanges That Just Won't Die
For a paper, one can tell what category it belongs to, by the keywords of the paper and the journal/proceeding where it is published, even though he is totally unfamiliar with the topic of the paper.
I wonder if there are some ways to tell what category a book belongs to?
One cannot look at its content or abstract, not even its title (I put this restriction, because in reality, even does so, if not familiar with the topic of the book, it is still hard to tell what category it belongs to).
The only available information is just any meta information available, either printed in the first few pages of the book or available on some websites that provide such information for categorization.
I also hope to be able to reach as fine category as possible/available.
Tim
Before I start, I'm a public librarian.
I refer to the CIP (Cataloging in Publication; on the verso of the title page) in assisting with determining at least a starting point about how to classify a book. If I still need help, I'll use WorldCat to find out what other libraries have done with the book.
Between these two places, and a willingness (and the time) to research Dewey numbers, I arrive at a call number that I feel the book belongs at and will circulate under.
Looking up a book in WorldCat will often give you subject information about it. See, for example, this introductory textbook on cataloging; to the right of the page you see its subject headings:
If that's not enough, you can click "View all subjects" for a longer list (often including subject headings in different languages).
For a quick and dirty category, if you don't have access to the internet, there are three main places that I look to see if the publisher has made it easy on me. (note, I'm doing this for dealing with book sales from the Friends of the Library, so it's more like bookstore categorization, not a fully detailed classification):
Of course, these have the problem that this is where the publisher wants you to put the book ... so pseudo science may claim to be science, etc.
If it's an older book (pre-2000?), it's less likely to have any of these.
And, when in doubt, you just file everything under 'inspirational' (memoirs, biographies, self-help, christian living, etc.)
As Jorge Luis Borges, writer and director of the National Library of Argentina, wrote in 1952 about classification:
Notoriamente no hay clasificación del universo que no sea arbitraria y conjetural. La razón es muy simple: no sabemos qué cosa es el universo.
Nobody knows what category a book belongs to. One would first have to actually read the book at least onece and read all related books or better every existing book. You can only select a category of your choice, based on:
The first in the end is guessing, but based on your experience. You look at title, cover, publisher, maybe the table of contents or any "meta information" quickly available. This judging with limited resources is what good librarians are required for. Sure you may use tools to facilitate decision, from a desk and references where to look up information about publishers and authors up to a computed tag cloud based on frequent words in the book.
The second requires to find these people and their selection. You may just ask somebody or look up how other librarians have categorized the book. Good resources include Amazon, LibraryThing, and Wikipedia.
So you may clarify whether you are looking for tools to better judge on your own or for sources of existing categorization.
The theoretical answer to the question is "no"; Patrick Wilson argued quite convincingly against the existence of a "correct" category. As Quine showed, there may be no "fact of the matter". http://en.wikipedia.org/wiki/Subject_(documents))
Though there may be many "correct" categories, there are vastly more incorrect categories, and it can be dangerous to simply guess without having access to the "book in hand". If a stub record needs to go in to the system to stop duplicates from being ordered, it is better to leave the subject blank, and put a SHOUTY BIG NOTE in the record saying to add headings when we get this.
If the item is already published, then checking the subjects and categories assigned by the Library of Congress is a good check. Before publication, they may rely on publisher supplied CIP information, which can be rather muddled.
It's also worth looking on worldcat.org and seeing what subjects have been assigned. There may be several records for a given book; the ones used by the most libraries are usually better than the ones that are only used by a few.
The most important rule is: If you don't know, don't just guess based on the title; if you guess wrong, the book may not be found by the patron who really needs it.
Every book its reader.