Discusses the literature that has become associated with Lotka's Law of Scientific Productivity (a general theoretical estimate of author productivity in the sciences) and attempts to identify the important factors of Lotka's original methodology that should be considered when attempting to test applicability of Lotka's Law. Forty-seven references…

Establishes a type-token identity relating type-token ratio and bilogarithmic type-token ratio; uses the Simon-Yule model of Zipf's law to drive the type-token ratio and provide a statistical model of text generation; and refines the model to allow for decreasing entry rates of new words. (26 references) (Author/CLB)

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)

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)

Illustrates that the Poisson-lognormal model provides good fits to a diverse set of distributions commonly studied in bibliometrics and scientometrics. Topics discussed include applications to the empirical data sets related to the laws of Lotka, Bradford, and Zipf; causal processes that could generate lognormal distributions; and implications for…

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…

Proposes and explains a modification of the mixed Poisson model for library circulations which takes into account the periods when a book is out on loan and therefore unavailable for borrowing. Highlights include frequency of circulation distributions; negative binomial distribution; and examples of the model at two universities. (Contains 34…

Develops stochastic model of library borrowing using Negative Binomial distribution applied to circulation data obtained from Huddersfield Public Library. Evidence concerning process of popularity decay is presented and method is given by which relegation tests can be constructed to maintain optimum turnover. Eight references and statistical…

Describes probabilistic document retrieval systems as a sequential learning process, in which the system learns the parameters of probability distributions describing the frequencies of feature occurrences in relevant and nonrelevant documents. Several techniques for estimating the parameters of distributions are described and the results of tests…

This paper examines a broad set of beliefs about achievement and the relationship of those beliefs to performance and future plans in mathematics and English. The two main purposes of the analysis are (1) to assess gender and grade-level differences in children's achievement beliefs as they proceed through junior and senior high school, and (2) to…