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Based on sample data representing five years of monthly circulation totals from 50 academic libraries in Illinois, Iowa, Michigan, Minnesota, Missouri, and Ohio, a study was conducted to determine the most efficient smoothing forecasting methods for academic libraries. Smoothing forecasting methods were chosen because they have been characterized as easy to use and fairly accurate. It was found that smoothing forecasting methods worked very poorly on monthly library data due to the seasonality present in monthly library circulation totals. The only method recommended for use with monthly data was Winters' Linear and Seasonal Exponential Smoothing method, which has a specific seasonal component. Much greater success was achieved by using smoothing forecasting methods with yearly-lagged data, for example, using the circulation totals of past Januarys to predict the total of a future January. The One-Month Single Moving Average was found to be the most efficient smoothing method for forecasting future monthly circulation totals on yearly-lagged data with litle or no trend, while Brown's One-Parameter Linear Exponential method (with alpha set at 0.5) was recommended for use in trending yearly-lagged data. These methods ranked first and second respectively in minimizing both the mean percentage forecasting error and standard deviation of forecasting errors. A 27-item bibliography and plots showing the circulation data from the 50 libraries are included. (ESR)

Analyzes relevance assessments of topical descriptors for bibliographic records for two dimensions: (1) a vertical conceptual hierarchy of broad to narrow descriptors, and (2) a horizontal linkage of related terms. The data were analyzed for a semantic distance and semantic direction effect as postulated by the Semantic Distance Model. (Author/LRW)

Presents and analyzes data from the 1992 AIDSLINE database on Acquired Immune Deficiency Syndrome and compares it with data from the 1989 AIDSLINE database regarding the shift in productivity of various journals and the changing frequencies with which Medical Subject Headings (MeSH) terms were used to provide subject access and control. (Author/LRW)

Reports on two experiments investigating the relationship between topical subject expertise and the assessment of relevance. Results indicate that topical subject expertise enhances effects of the semantic distance model (SDM), and that relevance assessment is a contingent, psychological phenomenon that is part of the human-perception task of online searching. (Author/JKP)

Describes applications in variety of settings of videodiscs as tools of information retrieval with online databases, identifies underlying technical capabilities, and discusses five operations required to implement any application: coordinating diverse formats; indexing; physically arranging items on disc; designing input, search, and output; modifying system. Seventeen sources are provided. (EJS)

Two sophisticated--autoregressive integrated moving average (ARIMA), straight-line regression--and two naive--simple average, monthly average--forecasting techniques were used to forecast monthly circulation totals of 34 public libraries. Comparisons of forecasts and actual totals revealed that ARIMA and monthly average methods had smallest mean absolute percentage error. (20 references) (EJS)

A sample of library-output statistics measuring circulation, reference, and in-library use was collected from 76 libraries and tested for redundancy, correlation, and variation using time-series analysis to test the Relative Fidelity of Measurement Model (RFM). The 275 sample statistics correlated in an unpredicted pattern. Twenty-three sources are provided. (EJS)