I’ve been thinking a lot about how booksellers and librarians can use LibraryThing for “readers advisory,” helping readers find books they’ll love. One answer, I think, is to promote and improve our “tagmashes” feature.

Readers Advisory is something of a discipline in librarianship, with a body of thinking behind it. There are also a number of well-known subscription RA tools, such as NoveList and FictonConnection, available in a very large number of US libraries. (See this page for a much larger list, which includes LibraryThing up with the big guys.)

LibraryThing can be used for Readers Advisory in a couple of ways:

• Some libraries have used LibraryThing to highlight special topics (eg., new YA material at the Framingham Library)
• Most LibraryThing works include recommendations—both automatic and member suggested, and with various summary and detailed lists—so you can get from a known book to a set of similar titles.  
• Our fielded wiki Common Knowledge links books by series, places, awards and so forth.
• LibraryThing tag pages provide relevancy-ranked lists for many topics, eg., chick lit, steampunk, memetics, cozy mysteries
• Tagmashes

“Tagmashes,” introduced a year ago, are a variant on tags, for when a simple tag isn’t good enough.

By combining two or more tags, or excluding tags,  tagmashes extend tagging and nip away at some of the unique values of traditional subject classification—high granularity and hierarchy. Thus, although the tagmash France, wwii doesn’t have an explicit notion of hierarchy, it works something like the LCSH World War II, 1939-1945 — France. (And, of course, the LCSH tree is an artificial one—there’s nothing in the idea that makes France a branch of World War II more than World War II is a branch of France!)

Notably, the system doesn’t make tagmashes, users do. Once made, they “stick around,” and may appear on related tag and subject pages, with their overlap to that page listed, testimony that a particular combination of tags made sense to someone. The system could–but does not currently–track tagmashes for relevance and usage, pruning some and elevating others. And it could allow users to edit, rate or review them for useful and accuracy.

I have it in my head that tagmashes, particularly with these additions, are one stone in the bridge between “free tagging” and traditional classification, between algorithmic recommendations and hand-generated ones, between the physical past and the digital future.

I see a world of librarians and readers creating, spreading and editing book lists that don’t just “stay still”—depreciating over time, like a physical object—but shift and grow like a digital object can. And they wouldn’t be the same for everyone, like a physical object, but adapt to the reader, like only a digital object can.

Anyway, here are some tagmashes to play with:

• Young adult fiction involving magic — fiction, magic, young adult
• Fiction related to France during World War II — France, WWII, fiction
• Nonfiction related to France during World War II — France, WWII, -fiction
• Classic 19c. Russian novels — 19th century, classics, novel, russia
• Parenting from an Evangelical perspective — christian living, parenting
• Human sexuality from an Evangelical perspective — christian living, sex
• British colonialism — britain, colonialsm
• “Dog memoirs” (a big genre recently) — dogs, memoir
• “Drug memoirs” — drugs, memoir
• Non-religious homeschool books — homeschool, -catholic, -christian, -religion
• Chick lit taking place in Greece — chick lit, greece
• Romances involving zombies — romance, zombies
• Romances involving zombies and taking part in Greece — Null set