In this article, a Bayesian model selection approach is introduced that can select the best of a set of inequality and equality constrained hypotheses for contingency tables. The hypotheses are presented in terms of cell probabilities allowing researchers to test (in)equality constrained hypotheses in a format that is directly related to the data.…

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)

Empirical estimates of production frontiers and average production functions performed for selected public elementary school districts in California support the hypothesis of an optimal school size model. Some policy implications of the results are briefly analyzed. Appended are 16 references. (MLF)

A study comparing citations received by patents in given year to number received in subsequent years found that, even though influential patents remain influential, both highly and infrequently cited patents age at same rate. Distribution of patents by number of citations received is stable over time. (17 references) (EJS)

Describes a model which uses patron arrival rate, length of time on the terminal, and library service policies to determine the minimum number of terminals needed. The model is then used to compare the effects of various service policies on the minimum number of terminals. (CLB)

Examines relationships among the parameters of the Zipf size-frequency distribution as well as its sampling properties. Highlights include its importance in bibliometrics, tables for the sampling distribution of the maximal value of a finite Zipf distribution, and an approximation formula for confidence intervals. (Author/LRW)

Proposes split model for index term distribution in document set that uses rank function for high frequency terms and size function for low frequency terms; the point of transition is determined either empirically or by rule. Distributions to describe index term exhaustivity and term co-occurrence are considered briefly. (36 references) (EJS)

The Generalized Inverse Gaussian-Poisson Distribution is suggested as an all-embracing mathematical model for bibliometric frequency distributions. Twelve examples are given which show that the new model cannot be rejected by virtue of an objective chi-squared test. A mathematical appendix and 20 references are included. (Author/EJS)

Describes the two basic approaches to the calculation of term discrimination values for automatic indexing. The results of an experiment that investigated the differences between algorithms of these two approaches in terms of their impact on the discrimination value model are reported and discussed. (13 references) (Author/CLB)

Frequency-of-circulation distributions from 16 United Kingdom libraries participating in initial period of operation of the Public Lending Right are discussed. Differences between the libraries are highlighted, and, for each, the adequacy of various refinements of the simplest model (geometric distribution, negative binomial distribution, or mixed…

The number of foreign professionals (including college students) who have entered the United States with nonimmigrant status but who have their visas adjusted to immigrant status is steadily increasing. This study explores the relationship between the frequency of such adjustments and changes in immigration policy. (PGD)

Review of recent developments in statistical theories for social sciences highlights Haitun's statistical distributions, Laplace's "Law of Succession" and distribution, Laplace and Bradford analysis of book-index data, inefficiency of frequency distribution analysis, Laws of Bradford and Zipf, natural categorization, and Bradford Law and…

Describes three studies concerned with learning to operate a control panel device and how this learning is affected by understanding a device model that describes its internal mechanism. Results indicate benefits of a device model depend on whether it supports direct inference of exact steps required to operate the device. (Author/MBR)

This study develops a three-stage model of the question-answering process and investigates several potential sources of extraneous variability. Discussion includes implications of findings concerning what it means to "use" library materials and services, adverbs used as response category labels, and subject's responses as predictors of…

Motivational design, a major component of the ARCS (Attention, Relevance, Confidence, Satisfaction) model that describes how to understand the motivation to learn, is described in this second article of a two-part series. Topics addressed include audience analysis; motivational objectives, measures, and motivational strategy design; and…