Comments on Progress Report: A Cost-Benefit Model of Some Critical Library Operations in Terms of Use of Serials (April 29, 1977) by Allen Kent and Others.

In their study of the usage demands placed on journal collections in academic libraries, Allen Kent and coauthors have not adequately considered the long-term variability of those demands in their formulation of a cost-benefit model for the management of journal collections. Though resource-sharing and the matching of periodical acquisitions to usage patterns can yield significant budgetary savings, the data gathering and data analysis techniques employed in Kent's study have limitations for predicting future use patterns and for making acquisitions decisions. The study fails to account for biases in usage patterns attributable to cyclical demands through the service day and academic year, and also fails to consider the intensity of journal use--quickly scanning an item counted as equivalent to reading it for several hours. Another shortcoming is the costly, labor-intensive aspect of Kent's technique: interviewers were used to contact individual journal users. Generalizing obsolescence rates over a group of titles is also questionable, for frequency of use as a function of age differs substantially between core and other journals with specific disciplines. Kent's study is useful in its development of a model for studying journal use, even though his methods are not satisfactory. (JL)