A simulation study by B. D. Wright and G. A. Douglas is critiqued, which indicates that the unconditional maximum likelihood method is an appropriate substitute for the theoretically superior conditional method for estimating parameters of the Rasch model. The study appears to rest on inadequate logic. (TJH)

Describes exploratory experiments in evaluating and improving a thesaurus through studying its effect on retrieval. A formula was developed to measure the conceptual distance between queries and documents encoded as sets of thesaurus terms. Comparison to the performance of people judging conceptual distance shows that the formula accurately…

Examples of two theory-based computerized learning systems--Smithtown and Sherlock--show that most success arises when learning tasks are well structured. Such systems teach procedural rather than conceptual knowledge and support individualized learning better than group learning. (SK)

Describes an empirical exploration of the instructional potential of virtual reality as an interface for simulation-based training. Shows that subjects learned spatial-procedural and spatial-navigational skills in virtual reality. (SR)

A simulation study compared the performance of the Mann-Whitney "U" test, Student's "t" test, and the alternate (separate variance) "t" test for two mutually independent random samples from normal distributions, with both one-tailed and two-tailed alternatives. Type I error probabilities were computed with equal and…

Sixty-three college students worked with a computer simulation in which gradually increasing model complexity (model progression), model progression plus small assignments, or a control condition without either were used. Definition knowledge increased for all three conditions, but intuitive knowledge gain was greater for the two experimental…

Hypothesizes that the construction of visual models, resolution of these visual models with numeric models and, in many cases, rejection of commitments such as the belief in one true velocity, are necessary for students to form integrated mental models of relative motion events. Studies high school students' relative motion problem solving.…

Investigates the effects of using molecular modeling on students' spatial ability, understanding of new concepts related to geometric and symbolic representations, and perception of the model concept. (Author/CCM)

Evaluates first-year college students' perceptions of molecular modeling. Examines the effectiveness, integration with course content, interests, benefits, advantages, and disadvantages of molecular modeling. (Author/CCM)

A hands-on group of seventh graders in technology education (n=29) used Legos and another group (n=29) used Gryphon Bricks simulation software for problem solving. Analysis of teacher ratings of solutions revealed no differences in creativity, originality, or usefulness of the products. (Contains 34 references.) (SK)

In this paper we discuss an experiment that was carried out with a prototype, designed in conformity with the concept of parallelism and the Parallel Instruction theory (the PI theory). We designed this prototype with five different interfaces, and ran an empirical study in which 18 participants completed an abstract task. The five basic designs…

In recent years, research efforts on complex systems have contributed to improve our ability in investigating, at different levels of complexity, the emergent behaviour shown by a system in the course of its evolution. The study of emergence, an intrinsic property of a large number of complex systems, can be tackled by making use of Cellular…

Current distance learning systems are increasingly packing highly data-intensive contents on servers, resulting in the congestion of network and server resources at peak service times. A distributed learning system based on faded information field (FIF) architecture that employs mobile agents (MAs) has been proposed and simulated in this work. The…

In track and field, gravity and air resistance act on the hammer after it has been released. Both of these forces depend on altitude and latitude. In addition, air resistance also depends on wind, temperature, humidity, and barometric pressure. Often, air resistance and varying gravity throughout the earth are not considered when throwing…

Continuing professional development (CPD) and life-long learning are vital to both individual and organisational success. For higher education, the intensive resource requirements requisite in the development of e-learning content and the challenges in accommodating different learning styles, developing an e-learning program can be a resource…