The main purpose of the present study is to predict the relationship between motivation , anxiety, perceived satisfaction and Second Life within asynchronous learning environment specifically in EFL course. Data of the present study were collected from undergraduate students - Sudan University of Technology and Science (SUST) in Sudan. The…

Studies comparing virtual and physical manipulative environments (VME and PME) in inquiry-based science learning have mostly focused on students' learning outcomes but not on the actual processes they engage in during the learning activities. In this paper, we examined experimentation strategies in an inquiry activity and their relation to…

The purpose of this study was to examine the effects of answer copying on the ability level estimates of cheater examinees in answer copying pairs. The study generated answer copying pairs for each of 1440 conditions, source ability (12) x cheater ability (12) x amount of copying (10). The average difference between the ability level estimates…

The predicted scores produced by regression with (1) single best predictor, (2) two best predictors, (3) all predictors with observed values, and (4) all predictors with or without observed values were compared with variable means as estimates of missing values. The study was conducted in a simulation mode on nx8 data matrices using various levels…

Discrete-time survival analysis is a new method for educational researchers to employ when looking at the timing of certain educational events. Previous continuous-time methods do not allow for the flexibility inherent in a discrete-time method. Because both time-invariant and time-varying predictor variables can now be used, the interaction of…

Analytical solutions for point and variance estimators of the mediated effect, the ratio of mediated to direct effect, and the proportion of the total effect mediated were determined through simulation for different samples. The sample sizes needed for accuracy and stability are discussed with implications for mediated effects estimates. (SLD)

Described in the context of a computer simulation are highlights of a program of research focusing on the storage of mathematics problem solving information in young children's memory and the development of such knowledge structures in older children. Specifically discussed are the problem size effect, the network nature of the memory…

There are times in survey research when missing values need to be estimated. The robustness of four variations of regression and substitution by mean methods was examined using a 3x3x4 factorial design. The regression variations included in the study were: (1) regression using a single best predictor; (2) two best predictors; (3) all available…

The stepwise regression method of selecting predictors for computer assisted multiple regression analysis was compared with forward, backward, and best subsets regression, using 16 data sets. The results indicated the stepwise method was preferred because of its practical nature, when the models chosen by different selection methods were similar…

This study examined the effect of three aspects of the testing context--physical privacy, anonymity, and offers of help from a tester--on children's expectations. Performance of 96 11-year-old boys and girls on a pictorial recall memory task in a simulated test was evaluated. The subjects were divided into eight different groups varying on the…

This paper discusses the principles underlying discriminant analysis and constructs a simulated data set to illustrate its methods. Discriminant analysis is a multivariate technique for identifying the best combination of variables to maximally discriminate between groups. Discriminant functions are established on existing groups and used to…

Guidelines for articulation of a framework for practical application of proportional-hazards models (PHMs) to professional survival analysis are provided. Focus is on data analysis fitting the PHMs with the semi-parametric methods of partial likelihood; this strategy is available in the BMDP2L and SAS PROC PHGLM computer programs. Areas in which…

Validity generalization meta-analysis (VG) examines the extent to which the validity of an instrument can be transported across settings. VG offers correction and summarization procedures designed in part to remove the effects of statistical artifacts on estimates of association between criterion and predictor. By employing a random effects model,…

This report for researchers in rural sociology develops a conceptual and analytic framework for evaluating policies or programs through interrelated models. Three models--structural analysis, control programming, and simulation--allow researchers to assess policy/program impact, determine why expected impacts did or did not occur, and modify…

This study used Markov chain matrices to simulate the effect of varying degrees of change in student characteristics on retention and graduation rates. Data were applied to a 1-year enrollment transition matrix that tracks how students of each class level progress into the same or higher class levels, to a completed degree, or to non-returning…