I’ve been having a few email discussions relating to whether or not it’s best to use a standard dictionary of words for an OPAC spellchecker or an index created from the actual holdings of that library…
pros: correct spelling
cons: suggestion might not find any results, might not contain buzz/new words
pros: suggestions should find results
cons: will contain mis-spellings (e.g. “mangement”), needs regular updates, might be difficult to extract the words from ILS/LMS/OPAC
I’m beginning to think that the best of both worlds might be to start with a standard dictionary and then let your users/patrons build upon that. In other words, whenever someone carries out a successful keyword search on the OPAC, automatically add the keyword(s) they used to your dictionary so that they can appear as spelling suggestions in the future.