The Cattell-Horn-Carroll (CHC) or three-stratum model of intelligence envisions human intelligence as a hierarchy. General intelligence (g) is situated at the top, under which are a group of broad intelligences such as verbal, visuospatial processing, and quantitative knowledge that pertain to more specific areas of reasoning. Some broad…

The worst performance rule (WPR) describes the phenomenon that individuals' slowest responses in a task are often more predictive of their intelligence than their fastest or average responses. To explain this phenomenon, it was previously suggested that occasional lapses of attention during task completion might be associated with particularly…

In this meta-study, we analyzed 2442 effect sizes from 131 meta-analyses in intelligence research, published from 1984 to 2014, to estimate the average effect size, median power, and evidence for bias. We found that the average effect size in intelligence research was a Pearson's correlation of 0.26, and the median sample size was 60. Furthermore,…

The utility of music training in schools has received much attention in the United States. The purported positive cognitive benefits of music training for schoolchildren is one facet which has historically been used to advocate for the existence of public school music programs. The purpose of this study was to conduct a random-effects…

The putative effectiveness of working memory (WM) training at enhancing cognitive and academic skills is still ardently debated. Several researchers have claimed that WM training fosters not only skills such as visuospatial WM and short-term memory (STM), but also abilities outside the domain of WM, such as fluid intelligence and mathematics.…

Because of the Flynn effect, IQ scores rise as a test norm ages but drop on the introduction of a newly revised test norm. The purpose of the current study was to determine the impact of the Flynn effect on learning disability (LD) diagnoses, the most prevalent special education diagnosis in the United States. Using a longitudinal sample of 875…

The present study investigated changes in self-esteem, academic self-concept, intellectual self-concept, and social self-concepts of acceptance, assertion, relations with same-sex peers and relations with other-sex peers with 177 gifted students participating in a 16-day summer school in Germany. Students were assessed three times by self-report…

Despite previous articles dating back 80 years, the questions of whether and when to square correlations continue to puzzle and confuse researchers. In this editorial, I point out that correlations can serve two independent purposes: they can be measures of effect size in themselves and their function as regression coefficients can be used to…

Teachers are often asked to nominate students for enrichment programs for gifted children, and studies have repeatedly indicated that students' intelligence is related to their likelihood of being nominated as gifted. However, it is unknown whether class-average levels of intelligence influence teachers' nominations as suggested by theory--and…

Test anxiety and its correlates were examined with college students with and without specific reading disability (RD; n = 50 in each group). Results indicated that college students with RD reported higher test anxiety than did those without RD, and the magnitude of these differences was in the medium range on two test anxiety scales. Relative to…

Data from Norway were analyzed to evaluate early behavioral intervention for children with intellectual disabilities. The intervention group (n = 11) received approximately 10 hours per week of behavioral intervention; the eclectic comparison group (n = 14) received treatment as usual. After 1 year, changes in intelligence and adaptive behavior…

In higher order factor models, general intelligence (g) is often found to correlate perfectly with lower-order common factors, suggesting that g and some well-defined cognitive ability, such as working memory, may be identical. However, the results of studies that addressed the equivalence of g and lower-order factors are inconsistent. We suggest…

Recently, different methodological approaches have been discussed as an explanation for inconsistencies in studies investigating sex differences in different intelligences. The present study investigates sex differences in manifest sum scores, factor score estimates, and latent verbal, numerical, figural intelligence, as well as fluid and…

Considerable debate exists regarding the accuracy of intelligence tests with members of different groups. This study investigated differential predictive validity of the "Wechsler Intelligence Scale for Children-Fourth Edition". Participants from the WISC-IV--WIAT-II standardization linking sample (N = 550) ranged in age from 6 through…

The Naglieri Nonverbal Ability Test, Second Edition (NNAT2), is used widely to screen students for possible inclusion in talent development programs. The NNAT2 claims to provide a more culturally neutral evaluation of general ability than tests such as Form 6 of the Cognitive Abilities Test (CogAT6), which has Verbal and Quantitative batteries in…