Curated databases

Curated databases are databases that are populated and updated with a great deal of human effort. Most reference works that one traditionally found on the reference shelves of libraries -- dictionaries, encyclopedias, gazetteers etc. -- are now curated. Since it is now easy to publish databases on the web, there has been an explosion in the number of new curated databases used in scientific research. The value of curated databases lies in the organization and the quality of the data they contain. Like the paper reference works they have replaced, they usually represent the efforts of a dedicated group of people to produce a definitive description of some subject area. databases present a number of challenges for database research. Because they are heavily crossreferenced with, and include data from, other databases, the topics of provenance and citation are ; as is annotation, since of much of the work of a curator is annotating existing data. Because these databases often evolve from semistructured representations, and because they have to accommodate new scientific discoveries, evolution of structure is important. Much of the work in these areas is in its infancy, but it is beginning to suggest new research for both theory and practice. We discuss of this research and emphasize the need to find appropriate models of the processes associated with curated databases.