Identifies four components of a good predictive lossless image compression method: (1) pixel sequence, (2) image modeling and prediction, (3) error modeling, and (4) error coding. Highlights include Laplace distribution and a comparison of the multilevel progressive method for image coding with the prediction by partial precision matching method.…

Discusses the problem of determining an adequate sample size for an information retrieval experiment comparing two systems on separate samples of requests. The application of statistical methods to information retrieval experiments is discussed, the Mann-Whitney U Test is used for determining minimum sample sizes, and variables and distributions…

Discussion of informetric distributions shows that generalized Leimkuhler functions give proper fits to a large variety of Bradford curves, including those exhibiting a Groos droop or a rising tail. The Kolmogorov-Smirnov test is used to test goodness of fit, and least-square fits are compared with Egghe's method. (Contains 53 references.) (LRW)

Describes a technique for statistically comparing bibliometric models and illustrates its use with two examples using Lotka's hypothesis of author productivity and one example using library circulation frequencies. Topics discussed include nested statistical models, analysis of variance, regression, log-linear models, and the likelihood ratio…

Summarizes the experimental evidence that indicates that text indexing systems based on the assignment of appropriately weighted single terms produce retrieval results superior to those obtained with more elaborate text representations, and provides baseline single term indexing models with which more elaborate content analysis procedures can be…

Describes study that compared terminology indexing and citation indexing to determine the similarity of documents retrieved. Information science articles from 1971 to 1983 in three journals were studied for term co-occurrences. The distinction between relevant and pertinent documents is discussed, and further research topics are suggested. (LRW)

This second report on a two-part study on the application of informetrics to information retrieval (IR) system design used models of database contents in a factorial simulation study at the University of Western Ontario. The study explored whether different file structures were better suited for different informetric environments. (32 references)…