Discussed are various models proposed for the Moebius strip. Included are a discussion of a smooth flat model and two smooth flat algebraic models, some results concerning the shortest Moebius strip, the Moebius strip of least elastic energy, and some observations on real-world Moebius strips. (KR)

The fit of the 3-parameter model on data from tests of cognitive ability was compared to the fit of the Ability Removing Random Guessing model of M. I. Waller (1973). Three cohorts of about 1,000 children (fourth, seventh, and tenth graders) each were administered examinations in 11 content areas. (SLD)

Analyzes a sample of over 4,700 orders for library materials at the University of California, Berkeley, in terms of the probability that the material will arrive and the factors that determine arrival. Models to evaluate the book ordering process are presented, and variables that may affect arrival time are discussed. (six references) (Author/LRW)

Describes the use of oceanographers' models for introducing students to the concept of mathematical modeling. Outlines a lesson showing the interrelationship of science and mathematics. (RT)

Uses citation data to examine the pattern of diffusion in the academic literatures of the sciences, social sciences, and the arts and humanities. Identifies a mathematical model which describes this pattern, and notes that this model, unlike linear models, describes the processes of both adoption and disadoption of an innovation. (MM)

A generalized Rasch model is presented for measuring attitudes; it is based on the concepts of Thurstone's method of successive intervals. Benefits of the model are illustrated with a study of students' (N=4,035 fifth through ninth graders) interest in physics. (SLD)

Discusses three types of bridges to determine how best to model each one: (1) drawbridge; (2) balance bridge; and (3) bascule bridge. Describes four experiments with assumptions, analyses, interpretations, and validations. Provides several diagrams and pictures of the bridges, and typical data. (YP)

Uses manipulative materials to build and examine geometric models that simulate the self-similarity properties of fractals. Examples are discussed in two dimensions, three dimensions, and the fractal dimension. Discusses how models can be misleading. (Contains 10 references.) (MDH)

Validated models of mental addition processing by testing children and adults in a production task paradigm. Examined individual-difference relations between strategy choice parameters and criterion-related measures of ability. Found that individual differences in the apparently calculative processes that underlie numerical facility are highly…

The specification and estimation of school effects, the variability of effects across schools, and the proportion of variation in student outcomes attributable to differences in school context and practice are considered. A statistical model is presented that defines school effects for parents choosing a school and for agencies evaluating school…

Presents two methods of calculating the expected value for a participant on the television game show "The Wheel of Fortune." The first approach involves the use of basic expected-value principles. The second approach uses those principles in addition to infinite geometric series. (MDH)

The intuitive simplicity of probability can be deceiving. Described is a dialogue that presents arguments for conflicting solutions to a seemingly simple problem determining the probability of having two boys in a two-child family knowing that one child is a boy. Solutions contain multiple arguments and representations. (MDH)

Presents an approach to the concept of absolute value that alleviates students' problems with the traditional definition and the use of logical connectives in solving related problems. Uses a model that maps numbers from a horizontal number line to a vertical ray originating from the origin. Provides examples solving absolute value equations and…

Discusses the equation and proportion methods for teaching how to solve percent problems. Supplements the teaching of each method by introducing a representational model that enhances understanding when solving percent problems. (MDH)

Describes advances in capture-recapture modeling, including the biologically motivated emphasis on model-based hypothesis testing and the development of models for spatially stratified populations. Discusses the severe problems associated with count statistics reflecting unknown sampling fractions. (67 references) (KR)