Representatives from the Michigan Department of Education and the Center for Educational Performance and Information requested assistance in estimating Michigan's capacity to adequately staff its high schools to meet the course requirements of the new Michigan Merit Curriculum. The study team devised a formula to estimate the number of additional…

This is a quantitative empirical research study validating the invariance of item difficulty parameters estimates based on the two competing measurement frameworks, the classical test theory (CTT) and the item response theory (IRT). In order to achieve the set goal, one fifty five (155) different independent samples were drawn from the population…

The study investigated the mental models of primary school children related to the day/night cycle. Semi-structure interviews were conducted with 40 fourth-grade and 40 sixth-grade children. Qualitative and quantitative analysis of the data indicated that the majority of the children were classified as having geocentric models. The results also…

The randomized response technique ensures that individual item responses, denoted as true item responses, are randomized before observing them and so-called randomized item responses are observed. A relationship is specified between randomized item response data and true item response data. True item response data are modeled with a (non)linear…

The purpose of this study was to investigate undergraduate students' performance while exposed to complementary computational modelling activities to improve physics learning, using the software "Modellus." Interpretation of kinematics graphs was the physics topic chosen for investigation. The theoretical framework adopted was based on Halloun's…

This study compared mortality among Danish citizens with autism spectrum disorders (ASDs) with that of the general population. A clinical cohort of 341 Danish individuals with variants of ASD, previously followed over the period 1960-93, now on average 43 years of age, were updated with respect to mortality and causes of death. Standardized…

In this note we develop a framework that makes explicit the inherent dynamic structure of certain mathematical definitions by means of the four facets of context-entity-process-object. These facets and their interrelations are then used to capture and interpret specific aspects of student constructions of the concept of solution to first order…

When the errors in an ordinary least squares (OLS) regression model are heteroscedastic, hypothesis tests involving the regression coefficients can have Type I error rates that are far from the nominal significance level. Asymptotically, this problem can be rectified with the use of a heteroscedasticity-consistent covariance matrix (HCCM)…

We show a new approach, based on the utilization of Matlab and Mathematica, for solving liquid-liquid extraction and binary distillation problems. In addition, the author shares his experience using these two softwares to teach equilibrium staged separations at the National Institute of Applied Sciences and Technology. (Contains 7 figures.)

Recent international studies have highlighted the success of students from Hong Kong in mathematics and problem-solving, and have begun to suggest some of the factors associated with this success. Other studies have suggested that Hong Kong students are averse to risk-taking, favouring memorisation and imitation in their solution strategies. Year…

The aim of this experiment is to study and calculate the kinetic constant of a Heck reaction: the arylation of but-3-en-2-ol by iodobenzene catalyzed by palladium acetate in presence of triethylamine in DMF. The reaction leads to a mixture of two ketones. Students use GC analysis to quantify reagents and products of reaction. They control the…

This article presents a new algorithm for computerized adaptive testing (CAT) when content constraints are present. The algorithm is based on shadow CAT methodology to meet content constraints but applies Monte Carlo methods and provides the following advantages over shadow CAT: (a) lower maximum item exposure rates, (b) higher utilization of the…

To date, few studies have investigated the evolution of problem solving and general numeracy abilities during adulthood: skills that have obvious social importance. In this research, evolutions in adults' mental arithmetic skills were investigated using data from the IVQ 2004 French national survey, which tested 9,185 adults aged between 18 and…

Recent advances in testing mediation have found that certain resampling methods and tests based on the mathematical distribution of 2 normal random variables substantially outperform the traditional "z" test. However, these studies have primarily focused only on models with a single mediator and 2 component paths. To address this limitation, a…

The authors propose a concise formula to evaluate the standard error of the estimated latent variable score when the true values of the structural parameters are not known and must be estimated. The formula can be applied to factor scores in factor analysis or ability parameters in item response theory, without bootstrap or Markov chain Monte…