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A Study of the Problem of the Aging of Books in University Libraries: Strategies for Countering Its Effects

This study reviews and analyzes the problem of aging of books in university libraries. Indexes are proposed for judging the aging process including the aging time limit, the over‐age book rate, and the aging rate. Based on these indexes, a mathematical model of the aging process is established, reduced to an algebraic equation, and calculated by a simple recurrence formula. The Mean Unit Price (MUP), an economic factor, is introduced. By using a dynamic model, a prediction of the time sequence of the MUP is made and a number of countermeasures are proposed for the control or retardation of the aging process. An index of economic benefit is introduced, using the principles of input‐output analysis, for the appraisal of the effectiveness of the countermeasures. Through appraisal and comparison, it is found to be more beneficial to eliminate some of the over‐age books first and then to work on collection planning in accordance with the predetermined aging rate and the rate of increment of the book collection capacity. © 1992 John Wiley & Sons, Inc.