Urquhart's Law: Probability and the Management of Scientific and Technical Journal Collections Part 3. The Law's Final Formulation and Implications for Library Systems.

This is the last part of an analysis of the law formulated by Donald J. Urquhart in respect to the use of scientific and technical (sci/tech) journals through either interlibrary loan or central document delivery. The first part discussed the genesis of this law as well as its statistical bases; the second dealt with the implications of the law for the development and management of the sci/tech journal collection of a central document delivery library. Part 3 concentrates on its consequences for all the libraries of a given library system. There is analyzed in this part the controversy over the validity of this law that caused Urquhart to formulate it in an explicit manner Part 3 discusses studies at various libraries that have corroborated this law, postulating that this law forces a probabilistic re-conceptualization of the functioning of the sci/tech journal system. Throughout this part, there are noted the consequences of the law for such matters as sci/tech journal sales, resource sharing, document delivery, interlibrary loan, and the transition from individually held paper copies of journals to shared electronic databases. [ABSTRACT FROM AUTHOR]