In the 1930s, Bernstein pointed out that more than one motor signal can trigger the same physical movement and that identical motor signals can lead to different movements, a dilemma that continues to puzzle scientists. Based on results from computer simulations, posits that these motor signals can be grouped into categories that correspond to…

The effect of scale selection on error in calibrating item and ability parameters was investigated, with particular reference to the standardized mean-squared difference (SMSD) statistic. Through simulation, three scaling methods for selecting the common scale were used to demonstrate their effects on SMSD values. (SLD)

Presents a four-part theoretical treatment of the planning of speech movements that favors models in which the only invariant targets are regions in auditory perceptual space over models that posit invariant construction targets. Computer simulations illustrate the models. (SLD)

The observed effectiveness and efficacy of discovery learning in simulated environments is reviewed, along with problems learners may encounter in discovery learning. How simulations can be combined with instructional support is discussed. Successful discovery learning is related to reasoning from hypotheses, applying the discovery process, and…

It is argued that outlier-prone distributions reduce the power of nonparametric tests, but power can be restored through procedures usually associated with parametric tests. Computer simulation is used to show how an outlier detection and downweighting procedure augments the power of the t-test and the Wilcoxon-Mann-Whitney test. (SLD)

The effects of different degrees of smoothing on results of equipercentile equating in random groups design using a postsmoothing method based on cubic splines were investigated, and a computer-based procedure was introduced for selecting a desirable degree of smoothing. Results suggest that no particular degree of smoothing was always optimal.…

Discusses challenges in teaching lasers and optical communications to engineers, including the prohibitive cost of laboratory experiments, and describes the development of a computer-based photonics simulation experiment module which provides students with an understanding and visualization of how lasers can be modulated in telecommunications.…

A new generation of e-learning companies is bringing the qualities of live role play to computer simulation. Successful simulations require authentic and relevant scenarios, situations that tap emotions and force actions, unrestricted options, and replayability. (JOW)

Visual-spatial ability has been identified as one of the primary factors of intelligence. Numerous tests, including paper-and-pencil tasks and laboratory experiments, have attempted to provide an accurate measure of this ability. However, the majority of these tests serve only as surrogate measures of visual-spatial ability and may not provide a…

Prior studies of time-to-contact (TTC) focused on judgments of unoccluded approaching objects. P. R. DeLucia, M. K. Kaiser, J. M. Bush, L. E. Meyer, and B. T. Sweet (2003) showed that partial occlusion decreases an object's optical size and expansion rate and that the value of tau derived from the reduced optical size (relative rate of accretion;…

In 4 experiments, the authors varied the extent and nature of participant movement in a virtual environment to examine the influence of action on estimates of geographical slant. Previous studies showed that people consciously overestimate hill slant but can still accurately guide an action toward the hill (D. R. Proffitt, M. Bhalla, R.…

It is the universal cry of parents the world over, driven mad by the persistent sight of their children investing hours and hours in mastering the many layers of a video game. To the parent, video games are the enemy, the nemesis of homework and learning. But the child sees something of value, something engaging enough to fill a weekend, to the…

Considerable research has compared how students learn science from computer simulations with how they learn from "traditional" classes. Little research has compared how students learn science from computer simulations with how they learn from direct experience in the real environment on which the simulations are based. This study compared two…

The spatial knowledge of 18 children with spina bifida and 18 healthy control children (matched according to sex, age, and verbal IQ) was investigated in a computer-simulated environment. All children had to learn a route through a virtual floor system containing 18 landmarks. Controlling for cognitive abilities, the results revealed that children…

Many credentialing agencies today are either administering their examinations by computer or are likely to be doing so in the coming years. Unfortunately, although several promising computer-based test designs are available, little is known about how well they function in examination settings. The goal of this study was to compare fixed-length…