Presents a relational logical model to support a sophisticated document retrieval system in which flexible forms of inferential and associative searching can be performed, and provides examples of ad hoc inquiries. Several problems of particular importance to document retrieval are discussed in terms of this model. (27 references) (Author/CLB)

Describes a computer simulation called "Supercontinent Aggregation and Dispersal" designed to model the interplay between the movement of the continents and the flow patterns of rock in the mantle. Discusses the strengths and weaknesses of the program in relation to the effects of continents on the mantle. (CW)

Genetic and environmental correlations among 11 Wechsler Intelligence Scale for Children-Revised (WISC-R) subtests were estimated from a sample of 143 twin pairs using the methodology of multivariate behavioral genetics. Correlations due to within-pair environmental influences were generally small, whereas those due to shared environmental…

Attempts to raise some of the issues involved in incorporating mathematical modelling with classroom teaching, as well as providing some background for those unfamiliar with the area. (PK)

This section provides mathematical activities in reproducible formats appropriate for students in grades 8-10. The activity is designed to provide an experience in model building while developing the concept of slope. (PK)

Confirmatory factor analyses were used to evaluate the fit of four factor models to high school students' responses to Paivio's Individual Differences Questionnaire (IDQ). Results showed that the IDQ's structure is best represented by a multifactor, oblique model and that five of the factors identified by Paivio can be replicated using a 34-item…

Three frequently used response formats are compared via analysis of covariance structures. The cumulative results based on four data sets provided evidence inconsistent with previous research suggesting that these formats are interchangeable. The semantic-differential format is most preferred while in most cases the Stapel format is least…

The factorial structure of the Rotter Internal-External (IE) scale was examined. While there was strong evidence against the unidimensionality of the Rotter scale, the findings suggested that the first-order factors do define a single higher-order construct that may represent the generalized IE construct. (Author/LMO)

Barcikowski has provided tables for use in situations where means are to be used as the unit of analysis. This article argues that the conditions specified for use of these tables are not practical. It explicates a methodology for carrying out analyses based on group means. (Author/JAZ)

To facilitate meta-analysis of diverse study findings, a mixed linear model with fixed random effects is presented and illustrated with data from teacher expectancy experiments. The standardized effect size is viewed as random and the variation among effect sizes is modeled as a function of study characteristics. (Author/BS).

Activities are presented to give students a picture of decimal concepts of tenths and hundredths. Three models (linear, regional, and value) are described, followed by four activities. (MNS)

Addressing the shortcomings of classical item statistics for selecting criterion-referenced test items, this paper describes an optimal item selection procedure utilizing item response theory (IRT) and offers examples in which random selection and optimal item selection methods are compared. Theoretical advantages of optimal selection based upon…

The need to provide understandable problems and ways to help children understand problems are explored. An interview with a sixth grader depicts his incorrect strategies and leads to suggestions for teaching problem solving using a range of mathematical models for each operation. (MNS)

Using observational data on classroom teachers, statistical procedures are presented for studying two questions on the stability of teacher behavior over time: (1) Is the individual teacher's behavior consistent? and (2) Are individual differences among teachers consistent? Approaches and methods of previous temporal stability studies are…

Explores potential of mathematical theory of communication for information science and examines question of how to encode a message at time it is encountered for subsequent recall. Examples of problem, a prototype computer program and experiment, coding as embedding in associational nets, and nature of information are discussed. (Nine references.)…