circulation numbers look at recent circulation, with no consideration of the way certain books may change in popularity. Here we have a Domain expert without financial motive who is saying that the algorithm is inefficient.
Algorithms should inform book culling decisions made by the Librarian, but they shouldn't replace the Librarian's knowledge and expertise.
I don't use our local library system much because they stock few or no copies of the things I'm interested in getting from them, like non-fic outside the poppiest of pop-non-fic—not even hardcore academic stuff necessarily, just not-garbage non-fic—math/computing books, and semi-obscure classics or translations. It's usually a waste of time to even check for those sorts of things there, and they don't even seem to be part of an inter-library loan program that can provide them.
How can circulation numbers take into account people who aren't using the library because it already doesn't have anything they want? I can't be alone in this, but simply looking at circulation numbers won't capture that, and piloting with a book or two from those categories won't get me back in (I probably won't notice because, after many disappointments, I've mostly stopped looking). Let an algorithm go nuts on that data without human judgement and I suspect you'll gradually put more and more people in my position, unless it's a damned smart one.
Any chance they have an interlibrary loan system? I can get all sorts of books from a variety of library systems (including the main state university libraries) delivered to my local town branch.
Interlibrary loan is great, not least because it's given us WorldCat, but it's no excuse for having a crappy collection. Libraries should of course add new things constantly, but the library is not just a lending club for poor people; it's meant to function as a repository of renewable intellectual content, and provide people with the opportunity to encounter ideas they might not otherwise.
1. Regular strategic planning which includes a community survey. This is conducted by an outside firm and non-users are targeted as part of the survey. We also do focus groups.
2. Interlibrary loan. You local library can likely get titles from other libraries. This should inform the collection.
3. Patron driven acquisition. Some way of suggesting books should be available. We buy most suggestions and find that books that are suggested circ better than ones selected by staff (generally, anyway).
Algorithms should inform book culling decisions made by the Librarian, but they shouldn't replace the Librarian's knowledge and expertise.