For decades, every chemical engineer has been asked to have a background in separations. The required separations course can, however, be uninspiring and superficial because understanding many separation processes involves conventional graphical methods and commercial process simulators. We utilize simple, user-­friendly mathematical software,…

Using construed data, it is demonstrated that the commonly-used method of showing mean salary by sex or mean salary by rank by sex can be misleading, and that a more realistic picture can be obtained using multiple regression analysis. Faculty staffing patterns were designed for two simulated institutions and is presented showing means and…

When changes occur in the number of credit hours demanded of a teaching unit, understanding of the sources of change is valuable policy making. Acceptable methods of determining sources of variance are not intuitively obvious, nor are the limitations of the simplest approaches. Sources of variance, not their causes, are discussed. Identification…

When looking at the relationship between individual earnings and schooling, there are potential sources of bias which arise due to individual education choices; individuals of higher unobserved ability or with higher unobserved payoffs from schooling may for instance invest more in education. This paper reviews alternative models and estimation…

The purpose of this study was to examine the relations of various cognitive abilities and aspects of math performance with computational estimation skill among third graders. Students (n=315) were assessed on language, nonverbal reasoning, concept formation, processing speed, long-term memory, working memory, inattentive behavior, basic reading…

This article examines the relevancy of large-scale, quantitative methodologies in middle grades education research. Based on recommendations from national advocacy organizations, the need for more large-scale, quantitative research, combined with the application of more rigorous methodologies, is presented. Subsequent sections describe and discuss…

Objective: The purpose of this study was to assess heritability of activity, attention, and impulsivity by comparing young monozygotic (MZ) twins with dizygotic (DZ) twins using objective measures. Method: The OPTAx test is an infrared motion analysis to record the movement pattern during a continuous performance test. Seventeen MZ and 12 same…

The Data File Documentation reports on the procedures and methodologies employed during the Education Longitudinal Study of 2002 base year, first, and second follow-ups, with special emphasis on the second follow-up (2006). The document is designed to provide guidance for users of the restricted-use data as released in Electronic Codebook (ECB)…

Education researchers, practitioners, and policymakers alike are committed to identifying interventions that teach students more effectively. Increased emphasis on evaluation and accountability has increased desire for sound evaluations of these interventions; and at the same time, school-level data have become increasingly available. This article…

SCORIGHT is a very general computer program for scoring tests. It models tests that are made up of dichotomously or polytomously rated items or any kind of combination of the two through the use of a generalized item response theory (IRT) formulation. The items can be presented independently or grouped into clumps of allied items (testlets) or in…

This paper examines issues related to the statistical power of impact estimates for experimental evaluations of education programs. The focus is on "group-based" experimental designs, because many studies of education programs involve random assignment at the group level (for example, at the school or classroom level) rather than at the student…

Enzyme kinetics is a difficult subject for students to learn and for tutors to teach. During the practicals included in the biochemical courses at the Faculty of Chemistry of Universidad Nacional Autonoma de Mexico, we found that the students acquire good training in the calculations to obtain kinetic parameters such as K[subscript m], V[subscript…

This paper describes a classroom teaching experiment, concerning the concept of probability, with children aged 5 in a kindergarten school. The teaching experiment was based on constructivist and interactionist theories about the learning of school mathematics and lasted one month. The collection of the information was based on the tape-recorded…

Researchers studying monitoring accuracy currently use two different indexes to estimate accuracy: relative accuracy and absolute accuracy. The authors compared the distributional properties of two measures of monitoring accuracy using Monte Carlo procedures that fit within these categories. They manipulated the accuracy of judgments (i.e., chance…

Cognitive clusters from the Woodcock-Johnson III (WJ III) Tests of Cognitive Abilities that measure select Cattell-Horn-Carroll broad and narrow cognitive abilities were shown to be significantly related to mathematics achievement in a large, nationally representative sample of children and adolescents. Multiple regression analyses were used to…