email: losee at unc period edu

Controlled and uncontrolled indexing terminology and metadata may be converted from one to another. Decision criteria are developed that can be used to determine which terms should be assigned when converting vocabularies. Methods are developed for computing the parameters of these systems, as well as means for estimating the parameters when given limited information. These conversion techniques may be applied to thesaurus terminology, gene ontologies, topic maps, uncontrolled natural language terms, folksonomies, tags and labels on web pages, the presence or absence of a specific hyperlink, as well as to metadata. Rules are provided suggesting circumstances when controlled vocabularies are always superior to using uncontrolled vocabularies. ∗ Thanks to Earl Bailey and Lee Roush for comments on this manuscript. 1 1