Students can learn great lessons when placed in decision-making roles. Simulating a Senate confirmation hearing can give students a glimpse of how government works and a chance to evaluate historical figures and issues. Any simulation, however, is an imperfect imitation of a real event. Having to make a decision based on incomplete information…

The Educational Object Economy (EOE) emerged from research on end-user authoring tools for multimedia software and, by 1997, developed into a library of over 2000 freely available interactive simulations for learning. The organization's original goals and its ongoing interest in alternative methods of software authoring led to continuing…

During periods of high unemployment, many workers exhaust their unemployment insurance (UI) benefits before regaining employment. To help alleviate this problem, Congress created the extended benefits (EB) program, expanding the number of weeks of benefits available to UI recipients in high unemployment states. The EB program operates by…

Facts, or skills? Content, or process? Teachers of history and social studies teachers often lock horns over these questions, trying to define the nature of their field and its role in secondary education. Teachers of history often focus on content, presenting the past as a series of important people and events, an accumulated cultural lore that…

After the first observation of life under the microscope, it took two centuries of research before the "cell theory" was established. Luckily, today's teachers can take advantage of computer technology and speed up the discovery process in their classrooms. This article describes how computer-based instructional programs can be used to engage…

This article describes a project in which certain key concepts in probability were explored using graphics calculators with year 10 students. The lessons were conducted in the regular classroom where students were provided with a Casio CFX 9850 GB PLUS graphics calculator with which they were familiar from year 9. The participants in the…

Ignoring a level can have a substantial impact on the conclusions of a multilevel analysis. For intercept-only models and for balanced data, we derive these effects analytically. For more complex random intercept models or for unbalanced data, a simulation study is performed. Most important effects concern estimates and corresponding standard…

The likelihood ratio test statistic G[squared](dif) is widely used for comparing the fit of nested models in categorical data analysis. In large samples, this statistic is distributed as a chi-square with degrees of freedom equal to the difference in degrees of freedom between the tested models, but only if the least restrictive model is correctly…

Using evidence from eye-tracking studies, Van Gompel, Pickering, Pearson, and Liversedge (2005) have argued against currently implemented constraint-based models of syntactic ambiguity resolution. The case against these competition models is based on a mismatch between reported patterns of reading data and the putative predictions of the models.…

The effect of item parameters (discrimination, difficulty, and level of guessing) on the item-fit statistic was investigated using simulated dichotomous data. Nine tests were simulated using 1,000 persons, 50 items, three levels of item discrimination, three levels of item difficulty, and three levels of guessing. The item fit was estimated using…

If one rolls a coin across a chessboard and it comes to rest on the board, what is the probability that it covers some corner of one of the grid squares? The online magazine "Plus" (2004) posed this problem for students to solve. It is a useful problem for several reasons: it introduces the idea of probability in a continuous sample space, it has…

P. A. Frazier, A. P. Tix, and K. E. Barron (2004) highlighted a normal theory method popularized by R. M. Baron and D. A. Kenny (1986) for testing the statistical significance of indirect effects (i.e., mediator variables) in multiple regression contexts. However, simulation studies suggest that this method lacks statistical power relative to some…

How can cognitive load in visual displays of computer simulations be optimized? Middle-school chemistry students (N = 257) learned with a simulation of the ideal gas law. Visual complexity was manipulated by separating the display of the simulations in two screens (low complexity) or presenting all information on one screen (high complexity). The…

The purpose of this study was to examine the effect of a Socratic animated agent on user performance in a computer-based CD player disassembly simulation. Vocational Education students were randomly assigned to one of two versions of the simulation. One version offered text-based feedback in the form of statements; the other one featured an…

This article analyzes collaboration in a computer-supported learning environment based on the professional practices of mediation and dispute resolution. In so doing, it explores the nature of collaborative learning in a setting marked by competition as much as cooperation. Interviews with students suggest that the processes of collaborative…