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…

In a recent paper, Johnson, Bouchard, Krueger, McGue, and Gottesman (2004) addressed a long-standing debate in psychology by demonstrating that the g factors derived from three test batteries administered to a single group of individuals were completely correlated. This finding provided evidence for the existence of a unitary higher-level general…

The worst performance rule for cognitive tasks [Coyle, T.R. (2003). IQ, the worst performance rule, and Spearman's law: A reanalysis and extension. "Intelligence," 31, 567-587] in which reaction time is measured is the result that IQ scores correlate better with longer (i.e., 0.7 and 0.9 quantile) reaction times than shorter (i.e., 0.1 and 0.3…

This paper examines the distribution of national IQ in geographical space. When the heritability of IQ and its dependence on eco-social factors are considered from a global perspective, they suggest that the IQs of neighboring countries should be similar. Using previously published IQ data for 113 nations (Lynn, R., & Vanhanen, T., (2006). IQ and…

The stability of psychometric "g," the general factor of intelligence, is investigated in simulated correlation matrices and in typical empirical data from a large battery of mental tests. "G" is robust and almost invariant across methods of analysis. A reasonable strategy for estimating "g" is suggested. (SLD)

To determine whether the visuospatial n-back working memory task is a reliable and valid measure of cognitive processes believed to underlie intelligence, this study compared the reaction times and accuracy of performance of 70 participants, with performance on the Multidimensional Aptitude Battery (MAB). Testing was conducted over two sessions…

Members of 118 families were administered the Wechsler Adult Intelligence Scale; a cognitive test battery; and tests of visual, auditory, and figure memory. Factor analysis of memory scores resulted in four-factor solution. Significant spouse correlations and significant midparent-midchild regressions were found for some of the memory measures.…

Relationships between intelligence test scores and measures derived from reaction time and perceptual speed procedures were investigated. Only three reaction time measures produced correlations greater than .25 with a general intelligence factor. Test-retest reliability of reaction time measures was low. The reaction time-intelligence relationship…

Borkowski and Krause (1983) concluded that the locus of black-white intelligence differences lies in metaprocesses not elementary cognitive processes. However, some variables were difference scores with unacceptably low reliability. Magnitude comparisons of racial differences give a different picture of results; comparable differences in measures…

In a computerized video-game-like spatial ability measure administered to 94 university students, the number of target hits was correlated with verbal intelligence quotient. The dynamic spatial measure does not load substantially on a general intellectual ability factor, but it does provide additional evidence that dynamic spatial ability is…

The general intelligence factor (g) was investigated using 170 university students across three batteries of ability measures: (1) a short-term memory battery; (2) the Multidimensional Aptitude Battery; and (3) a reaction time battery. Results support the notion of g and suggest short-term memory as an essential aspect of intelligence. (SLD)