On the one hand, the factors Gf and Gc in the Cattell-Horn-Carroll (CHC) model of intelligence are hypothesized to represent individual differences in unique psychological or biological capacities. On the other hand, they are interpreted as representing the theoretical variables fluid and crystallized intelligence in investment theory. With…

Sex differences on the Attention Test (AC), the Raven's Standard Progressive Matrices (SPM), and the Brazilian Cognitive Battery (BPR5), were investigated using four large samples (total N=6780), residing in the states of Minas Gerais and Sao Paulo. The majority of samples used, which were obtained from educational settings, could be considered a…

Floyd, Shands, Rafael, Bergeron and McGrew (2009) used generalizability theory to test the reliability of general-factor loadings and to compare three different sources of error in them: the test battery size, the test battery composition, the factor-extraction technique, and their interactions. They found that their general-factor loadings were…

We examined the degree to which the conventional notion of g associated with IQ tests and general cognitive ability tests ("COG-g") relate to the general ability that underlies tests of reading, math, and writing achievement ("ACH-g"). Two large, nationally representative data sets and two independent individually-administered…

We examined whether the General Factor of Personality (GFP) is related to the "g" factor of cognitive ability using data from the Vietnam Experience Study which randomly sampled 4462 Vietnam War veterans from a total sample of about five million Vietnam era army veterans. Exclusionary criteria included passing a fitness test, achieving a…

Executive functions (EF) and intelligence are of critical importance to success in many everyday tasks. Working memory, or updating, which is one latent variable identified in confirmatory factor analytic models of executive functions, predicts intelligence (both fluid and crystallised) in adults, but inhibition and shifting do not (Friedman et…

Three prominent theories of intelligence, the Cattell-Horn-Carroll (CHC), extended fluid-crystallized (Gf-Gc) and verbal-perceptual-image rotation (VPR) theories, provide differing descriptions of the structure of intelligence (McGrew, 2009; Horn & Blankson, 2005; Johnson & Bouchard, 2005b). To compare these theories, models representing them were…

The general differentiation hypothesis states that the strength of the correlations among a set of IQ subtests varies with a given variable. Instances of the general differentiation hypothesis that have been considered in the literature include age and ability differentiation. Traditionally, the differentiation effect is attributed to the varying…

Factor analysis is arguably one of the most important tools in the science of mental abilities. While many studies have been conducted to make recommendations regarding "best practices" concerning its use, it is unknown the degree to which contemporary ability researchers abide by those standards. The current study sought to evaluate the typical…

The validity of cognitive ability tests is often interpreted solely as a function of the cognitive abilities that these tests are supposed to measure, but other factors may be at play. The effects of test anxiety on the criterion related validity (CRV) of tests was the topic of a recent study by Reeve, Heggestad, and Lievens (2009) (Reeve, C. L.,…

Mental chronometry (MC) studies cognitive processes measured by time. It provides an absolute, ratio scale. The limitations of instrumentation and statistical analysis caused the early studies in MC to be eclipsed by the "paper-and-pencil" psychometric tests started by Binet. However, they use an age-normed, rather than a ratio scale, which…

Researchers interested in working memory have debated whether it should be considered a single latent cognitive ability or a set of essentially independent latent abilities distinguished by domain-specific memory and/or processing resources. Simultaneously, researchers interested in cognitive aging have established that there are substantial…

This paper compares different theoretical models of the structure of intelligence, based on the analysis of data obtained in a series of measured abilities corresponding to the Spectrum assessment activities (Gardner, Feldman & Krechevsky, 1998) in a sample of 393 children enrolled in kindergarten and first grade. The data were analyzed using…

Although it is well established that preterms as a group do poorly relative to their full-term peers on tests of global cognitive functioning, the basis for this relative deficiency is less understood. The present paper examines preterm deficits in core cognitive abilities and determines their role in mediating preterm/full-term differences in IQ.…

To understand the extent to which the general-factor loadings of tests are inherent in their characteristics or due to the sampling of tests, the number of tests in the correlation matrix, and the factor-extraction methods used to obtain them, test scores from a large sample of young adults were inserted into independent and overlapping batteries…