Discussion of operational effectiveness in libraries focuses on a modeling approach that was used to compare the effectiveness of a local interlibrary loan system with using a national system, the British Library Document Supply Centre (BLDSC). Cost figures and surveys of five academic libraries are described. (six references) (LRW)

A general longitudinal model is presented for estimating school effects and their stability. The model, capable of separating true changes from sampling and measurement error, controls statistically for effects of factors exogenous to the school system. The model is illustrated with data from large cohorts of students in Scotland. (SLD)

Discussed is wavelet theory, which provides ways to rearrange data to reveal features of a physical or mathematical system which might otherwise be hidden. This theory is compared to fourier analysis and the advantages of wavelet theory are stressed. Applications of this technique are suggested. (CW)

Formulas are provided for estimating the reliability of a linear composite of non-equivalent subtests given the reliabilities of component subtests. The reliability of the composite is compared to that of its components. An empirical example uses data from 170 children aged 4 through 8 years performing 34 Piagetian tasks. (SLD)

Investigated the effect of the choice of a model's medium (algebraic expression or computer program) on the performance of students. Student programers did not transfer the qualities of a computer program approach to their algebraic models. Provides items for five tests. (YP)

It is suggested that some of the technology applied to state Scholastic Aptitude Test scores to measure states' educational performance (particularly use of a truncated Gaussian model) may make it possible to adjust National Assessment of Educational Progress (NAEP) scores to make inferences about state educational progress possible. (SLD)

Describes the definition and characteristics of a regular polyhedron, tessellation, and pseudopolyhedra with diagrams. Discusses the nature of simplex, hypercube, and cross-polytope in the fourth dimension and beyond. (YP)

A model and computation procedure based on classical test score theory are presented for determination of a correlation coefficient corrected for attenuation due to unreliability. Delta and Monte Carlo method applications are discussed. A power analysis revealed no serious loss in efficiency resulting from correction for attentuation. (TJH)

A meta-analysis of research on the relationship between inspection time (IT) and IQ was performed. The analysis was designed to determine whether a non-zero relationship between IT and IQ exists, estimate the size of this relationship, and test whether IT is ontogenetically related to "g" (intelligence). (TJH)

Middle school and college students were assessed on percentage. Better students in each group were given word problems involving percentage and asked to think aloud as they solved problems. College students made more use of strategies for control and monitoring of their own procedures. A three-stage model for problem solving is then hypothesized.…

Suggests ways in which mathematical models can be presented and developed in the classroom to promote discussion, analysis, and understanding of issues related to energy consumption. Five problems deal with past trends and future projections of availability of a nonrenewable resource, natural gas. (Contains 13 references.) (MDH)

A study involving 1,000 simulated examinees compared the partial credit and graded response models in computerized adaptive testing (CAT). The graded response model fit the data well and provided slightly more accurate ability estimates than those of the partial credit model. Benefits of polytomous model-based CATs are discussed. (SLD)

Reports a study designed to identify 9 and 11 year olds' ways of drawing nets of solids and to provide opportunities for them to reflect on their models in whole class discussions. Results indicated that children's views of solids' nets progressed from more global and holistic to more quantitative and analytic. (MDH)

Reviews the history of the concept of function, looks at its relationship with other sciences, and discusses its use in the study of real world situations. Discusses the process of constructing mathematical models of function and emphasizes the importance of the roles of the numerical, graphical, and algebraic representational forms. (MDH)

Discusses the mathematical model presented by Vito Volterra to describe the dynamics of population density. Discusses the predator prey relationship, presents an computer simulated model from marine life involving sharks and mackerels, and discusses ecological chaos. (MDH)