The demographic analysis of the educational process has been of great assistance to the work of educational planners, who must continually estimate the size of future student enrollments at different levels of the educational structure. (Author)

If one is given three or more methods of measuring three or more traits, the procedure described allows one to assess the extent to which the observation is influenced by the method and the extent to which individual differences contribute to the observations, independent of the particular method-trait combination. The procedure is illustrated.…

Mathematical modeling problems encountered in many disciplines are discussed in terms of the modeling process and applications of models. The models are classified according to three types of abstraction: continuous-space-continuous-time, discrete-space-continuous-time, and discrete-space-discrete-time. Limitations in different kinds of modeling…

This exercise in mathematical modelling requires understanding of geometric progressions, inequalities, and absolutes. It presents a problem on credit creation in the banking system. (MNS)

Helping children to bridge the gap between physical materials and symbolic representations is the focus of this article. Examples are drawn from numerical topics, with several hierarchies illustrated. (MNS)

Five models which perform search tasks of the Data Base Access and Search Environment (DBASE) are presented and used for comparison with subject search performance--unconstrained (rule-based, decision theoretic) and constrained (optimal rule-based, rule-based, probabilistic rule-based). Previous experiments and the modeling approach are briefly…

Discusses analytical design and experimental verification of a PID control value for a temperature controlled liquid delivery system, demonstrating that the analytical design techniques can be experimentally verified by using digital controls as a tool. Digital control instrumentation and implementation are also demonstrated and documented for…

A three-equation simultaneous regression model was developed with regular education spending, the prevalence of handicapped children, and handicapped spending as endogenous variables. A tentative test of the model was made using recently available data from the Wisconsin special needs assessment survey and supplementary special education aids…

An ignored aspect of standard setting, namely the possibility that Angoff or Nedelsky judges specify inconsistent probabilities (e.g., low probabilities for easy items but large probabilities for hard items) is explored. A latent trait method is proposed to estimate such misspecifications, and an index of consistency is defined. (Author/PN)

Derives the underlying structure of the Zipf distribution, with emphasis on its application to word frequencies in the inverted files of automatic bibliographic systems, and applies the Zipfian model to the National Library of Medicine's MEDLINE database. An appendix on the Zipfian mean and 12 references are included. (Author/JL)

Regression analysis of 1956-79 data on high school and college enrollment among males aged 16-21, minimum wage levels, military draft requirements, unemployment rates, family income, high school graduation, and job opportunities indicates that male enrollment rates respond strongly to changes in the expected rate of financial return to schooling.…

A multitrait-multimethod matrix containing two methods of measuring 12 personality traits was analyzed and confirmatory factor analysis was applied to the data. Although unexplained variance remained, method factors and a general personality factor significantly improved the fit of a model containing only trait factors. (Author/RL)

Argues that corporation trainers need to capitalize upon technological innovations to create more efficient and effective training programs, compares training alternatives, and provides models for determining costs for students, instructors, facilities, administration, and instructional development, as well as the total corporate training cost.…