Using data from the Trends in International Mathematics and Science Study (TIMSS) 2007, this study examined the big-fish-little-pond-effects (BFLPEs) in 49 countries. In this study, the effect of math ability on math self-concept was decomposed into a within- and a between-level components using implicit mean centring and the complex data…

Growth curve models with different types of distributions of random effects and of intraindividual measurement errors for robust analysis are compared. After demonstrating the influence of distribution specification on parameter estimation, 3 methods for diagnosing the distributions for both random effects and intraindividual measurement errors…

Using the Trends in International Mathematics and Science Study 2003 data, this study built mathematics achievement models of 8th graders in four countries: the USA, Russia, Singapore and South Africa. These 4 countries represent the full spectrum of mathematics achievement. In addition, they represent 4 continents, and they include 2 countries…

The current study aimed at identifying the differences in moral Judgment levels among female students according to their giftedness and grade levels. In specific, the study attempted to answer the following questions: (1) Does moral judgment differ due to the differences in giftedness and grade levels? (2) Is it possible to efficiently predict the…

There has been considerable interest in nonlinear latent variable models specifying interaction between latent variables. Although it seems to be only slightly more complex than linear regression without the interaction, the model that includes a product of latent variables cannot be estimated by maximum likelihood assuming normality.…

This study examines whether MidYIS and YELLIS cognitive ability tests (CATs) are appropriate methods for the identification of giftedness in Design and Technology. A key rationale for the study was whether CATs and able to identify those students with the aptitudes considered of importance to identifying giftedness in Design and Technology and…

This study examined the relationship between academic domain specific self-concept (specifically mathematical and verbal) and the academic achievement in mathematics and English of young adolescents. Middle school students in grades seven and eight ranging in age from 12 to 15 years completed three subscales of the Self-Description…