It is shown that Trueswell's empirical 80/20 rule arises from type of stochastic model for library loans presented by Burrell and Cane. Particular attention is paid to previously suggested uses of rule in identifying "core collection" for library noting that length of time period is of crucial importance. (20 references) (EJS)

Proposes a mathematical model using the probability formalism to explain why a geometrical law is observed in distributions related to library circulation data. Highlights include techniques based on convolution theory; Lotka's law; and Bradford's law. (Author/LRW)

Argues that the gamma mixture of Poisson processes, for all its perceived defects, can be used to make predictions regarding future library book circulations of a quality adequate for general management requirements. The use of the model is extensively illustrated with data from two academic libraries. (Nine references) (CLB)

Argues that library book circulation is a binomial rather than a Poisson process, and that individual book popularities are continuous beta distributions. Three examples demonstrate the superiority of beta over negative binomial distribution, and it is suggested that a bivariate-binomial process would be helpful in predicting future book…

Discusses the purpose of mathematical models and reviews the phases of the modeling process--defining performance, representing the problem, predicting performance, estimating parameters, defining optimization criterion, determining solution, and implementing results. Reviews of book-use, resource allocation, and library network models are…

Discussion of models for library circulation data highlights a new statistical prediction model that creates a flexible regression curve. Linear graphs that result from previous models are discussed, bivariate discrete distributions are explained, and graphs that show library circulation for one year at a time are presented. (nine references) (LRW)

Correlation structure of the Burrell and Cane mixed Poisson model for library loans with aging is presented and illustrated by data from University of Sussex. The approach is compared and contrasted with that originally formulated by Morse and recently reevaluated by Beheshti and Tague. Directions for future investigations are suggested. (Author)

Fuzzy set theory, a mathematical modeling technique that allows for the consideration of such factors as "professional expertise" in decision making, is discussed as a tool for use in libraries--specifically in collection management. The fundamentals of fuzzy set theory are introduced and a reference list is included. (JL)

Proposes a model of library output as an abstract quantity, and relates it to other components of library performance. The consequences of basing library funding on such measurable outputs as circulation are also examined in light of the proposed model. A 13-item reference list and four figures are provided. (JL)

Classical queuing theories and their accompanying service facilities totally disregard the human factors in the name of efficiency. As library managers we need to be more responsive to human needs in the design of service points and make every effort to minimize queuing and queue frustration. Five references are listed. (Author/RAA)

Discusses the generalized inverse Gaussian-Poisson (GIGP) process for informetric modeling. Negative binomial distribution is discussed, construction of the GIGP process is explained, zero-truncated GIGP is considered, and applications of the process with journals, library circulation statistics, and database index terms are described. (50…

Explains some observed library circulation frequency distributions through use of a simple stochastic model for the borrowing of books from a library collection. Parameters of the model are described and the model is applied to circulation data from three academic libraries. (Author/SW)

Presents a model of the relation between the circulation at a large library, the collection at that library, and the size of the user population. Analysis of data at United States academic research libraries reveals a square-root law describing this relation. Explores theoretical foundations and speculates on bibliometric implications. (Author/AEF)

Two models of library circulation, the Markov model and the mixed Poisson Model, are applied to circulation statistics from the University of Saskatchewan. Goodness-of-fit tests indicate that neither model fits the data; in both cases, the set of noncirculating items is larger than that predicted by the model. (Author/LRW)

Describes a computerized decision support system based on circulation data that was developed to assist the Indianapolis-Marion County Public Library in materials acquisition budgeting and other library management decision making. The budget allocation model is explained, and implementation and testing of the decision support system is described.…