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 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…

Discusses the interdependencies between parameter estimation and properties of probabilistic models, such as dependency assumptions, binary vs. nonbinary features, and estimation sample selection. An optimum estimation for binary features applicable to information retrieval is defined, a method for computing this estimation using empirical data is…

Argues that a major difficulty in using Lotka's law in information science arises from the misuse of goodness of fit tests in parameter estimation. Three approaches for studying Lotka's law are presented: an index approach, a time series approach, and a generating mechanism incorporating these two influential variables to derive an equilibrium…