Examines query expansion during query translation in cross language information retrieval and develops a general framework for inferential information retrieval in two particular contexts: using fuzzy logic and probability theory. Obtains evaluation formulas that are shown to strongly correspond to those used in other information retrieval models.…

Presents an alternative approach to teaching Mendelian genetics that includes the use of mathematical procedures and models to describe the occurrence and probabilities of heritable outcomes. Examples illustrate use of the method to calculate genotypic and phenotypic ratios for crosses involving multiple alleles with independent and dependent…

Presents an overview of Rasch measurement models that begins with a conceptualization of continuous experiences often captured as discrete observations. Discusses the mathematical properties of the Rasch family of models that allow the transformation of discrete deterministic counts into continuous probabilistic abstractions. Also discusses six of…

Presents a model of tests and measurement that identifies test scores with Hilbert space vectors and true and error components of scores with linear operators. This geometric point of view brings to light relations among elementary concepts in test theory, including reliability, validity, and parallel tests. (Author/SLD)

This seventh in a series of articles discussing expert system construction focuses on two ways to create a structure that determines a decision: (1) rule-based, or deductive, implementation; and (2) example-based, or inductive, implementation. Probability factors and confidence levels are discussed, and an example is given for selecting an…

Discusses the probabilities and positive and negative predictive values of medical tests for HIV. (MKR)

Discussion of authorship distributions focuses on the results of a numerical study for fractional authorship attribution. Highlights include coauthors; multinomial coefficients; Lotka functions; probability distributions of articles per author; and probability distributions of authors per article. (LRW)

The phenomenon of 2 x 2 x 2 arrays having nonmaximal rank with positive probability, pointed out by J. Kruskal (1989), is generalized to 2 x "n" x "n" arrays. It is concluded that a pair of asymmetric square matrices can be diagonalized simultaneously with positive probability. (SLD)

Discussion of probabilistic information retrieval (IR) systems challenges the probability ranking principle in IR from the perspective of (1) signal detection-decision theory and (2) utility theory. Calibration, certainty, and independent assessment are discussed in terms of the relevance of documents, and standard retrieval policies are analyzed.…

The phimax adjustment to phi (Pearson's product moment correlation applied to binary data) is explored. Phi/phimax is shown to be a measure of relationship apart from its affiliation with phi. The relations between phi/phimax and kappa and limitations of phi/phimax are discussed. (SLD)

A model for preferential and triadic choice is derived in terms of weighted sums of central F distribution functions. It is a probabilistic generalization of Coombs' (1964) unfolding model from which special cases can be derived easily. This model for binary choice can be easily related to preference ratio judgments. (SLD)

Reports on conditions under which people's probability judgments are superadditive rather than subadditive. Both directions of deviation from additivity are interpreted in a common framework, in which probability judgments are often mediated by judgments of evidence. The two kinds of nonadditivity result from differences in recruitment of…

Six- to 14-year olds added "winning" beads to an urn of "losing" beads in order to generate equal probabilities of choosing a winning bead from each of two urns. Found that 13-year olds integrated the two dimensions (winning and losing beads), the youngest children relied on one dimension, and 9- to 10-year olds partly combined…

Describes similarities and differences between additive conjoint measurement and the Rasch model, and formalizes some new nonparametric item response models that are, in a sense, probabilistic measurement theory models. Applies these new models to published and simulated data. (SLD)

Reports on a study designed to provide baseline data in the area of conjunction and conditional events. Cross-sectional and longitudinal analyses revealed improvement with grade in expressing probability numerically and distinguishing conditional events, but no change in incidence of conjunction errors. (Author/MM)