The testing effect, defined as the positive effect of "retrieval practice" (i.e., self-testing) on long-term memory retention relative to other ways to support learning, is a robust empirical phenomenon. Despite substantial scientific evidence for the testing effect, less is known about its effectiveness in relation to individual…

Little empirical data are available concerning the cognitive abilities of gifted individuals in general and especially those who excel in mathematics. We examined visual processing abilities distinguishing between general giftedness (G) and excellence in mathematics (EM). The research population consisted of 190 students from four groups of 10th-…

Confirmatory Factor Analysis was used to test first- and second-order factor models on cognitive abilities and their invariance across male and female samples. Subjects were a stratified random sample of 234 male and 225 female 15-year-old students in Singapore attending Secondary 3 (the equivalent of grade 9). Four first-order factors were found…