This analysis of Zipf's law uses an index for the sequence of observed values of the variables in a Zipf-type relationship. Three important properties relating rank, count, and frequency are identified, shapes of Zipf-type curves are described, and parameters of the Mandelbrot-Zipf law are discussed. (Author/LRW)

Discusses flaws in the Apple IIe Applesoft random number generator, RND, and reports results of frequency and serial correlation tests of the generator. Suggestions of seeds that yield sequences of numbers which pass fundamental screening tests for randomness are presented. (Author/LRW)

The focus of this simulation study was to investigate the effects of item difficulty drift on the stability of test taker ability estimates and pass/fail status under the Rasch model. Real, non-normal distributions of test taker abilities and item difficulties were used to represent true parameters. Test taker responses for 18 conditions of item…

Developed by B. Efron (1979) and his colleagues (P. Diaconis and B. Efron, 1983), bootstrap methods have the goal of creating an empirical sampling distribution that can be used to test statistical hypotheses, estimate standard errors, and create confidence intervals. Bootstrapping methods offer a unique and effective method for testing the…

Conducted simulations to explore methods for comparing bivariate distributions corresponding to two independent groups, all of which are based on Tukey's "depth," a generalization of the notion of ranks to multivariate data. Discusses steps needed to control Type I error. (SLD)

Relationships among the noncentrality parameter for the "F" distribution, mean square between and within groups, and effect size are examined. (Author)

Similarity between pairs of scores with a common mean and variance can be expressed in terms of the absolute differences between them. The distribution of such absolute differences between pairs of normally distributed scores with a common mean and variance is discussed, with procedures for calculating moments and areas within this distribution.…

Demonstrates visualization techniques using the tuple frequency method that helps organize data generated in computational studies of literary style. Two-dimensional representations of the style of the authors of "The Federalist Papers" are explained that were used to determine the authorship of unattributed papers. (Contains 13…

The accuracy of Kendall's chi square approximation (M. Kendall, 1962) to circular triad distributions was assessed by comparing estimated indices to enumerated values across upper and lower tails of cumulative proportions of circular triad distributions. In general, the approximation was found to be quite good, and its use is discussed. (SLD)

Describes available variance component tests and presents three new score tests. One test uses the asymptotic normal distribution of the test statistic as a reference distribution; the others use a Satterthwaite approximation for the null distribution of the test statistic. Evaluates the performance of these tests through Monte Carlo simulation.…

Discusses the concept of the hyperbolic or skew distribution as a universal statistical law in information science and socioeconomic studies. Topics include Zipf's law; Stankov's universal law; non-Gaussian distributions; and why most bibliometric and scientometric laws reveal characters of non-Gaussian distribution. (Author/LRW)

This paper discusses the reliance of numerical analysis on the concept of the standard deviation, and its close relative the variance. It suggests that the original reasons why the standard deviation concept has permeated traditional statistics are no longer clearly valid, if they ever were. The absolute mean deviation, it is argued here, has many…

The authors examined the confidence of teachers from Germany, Hong Kong, Italy, and the United States (N = 1,375) to address civic topics with their students. The authors also used differential item functioning models to examine responses to items from the Teacher Confidence Scale of the International Association for the Evaluation of Educational…

The present attempt is to study the use of computer and its possible relationship to Internet attitude, self-efficacy in computer and computer anxiety among higher secondary students. The present study aims at finding the levels of use of computer, Internet attitude, Self-efficacy in computer and computer anxiety among higher secondary students.…

Research Services calculates enrollment projections on an annual basis. These projections are presented each year at the district's Pupil Population Estimating Conference. For this year's projections, two years of trend data (2006-07 and 2007-08) were used to project student enrollment for 2008-09. Projections are provided by individual grade…