While professionally created metadata are often considered of high quality, it is costly in terms of time and effort to produce. User created metadata is a third approach, and this paper focuses on grassroots community classification of digital assets.
"we have to (...) merge and leverage emerging and traditional tools to improve findability. (...) at the intersection of those two models is a more powerful framework for identifying, sharing, and finding information. The goal is a metadata ecology"
"This presentation explores the results of the lexical analysis of various tag collections (...). What can we learn from human-generated metadata to help make automatically-generated metadata more usable, correct, efficient, and most importantly, humane?"
"controlled vocabularies often miss out on input from content authors and become rigid (...); folksonomies will begin to break down for the reasons mentioned above. Treating them as major parts of a single metada ecology might expose a useful symbiosis"
M. Magableh, A. Cau, H. Zedan, and M. Ward. Proceedings of the IADIS International Conferences Collaborative Technologies 2010 and Web Based Communities 2010, page 178--182. (July 2010)