In many developed cultures there is an assumption that IQ is intelligence. However, emerging theories of multiple intelligences, of emotional intelligence, as well as the application of IQ testing to other cultural groups, and to people with disability, raises many questions as to what IQ actually measures. Despite recent research that shows IQ…

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…

Owing to higher performance on the Raven's Progressive Matrices (RPM) than on the Wechsler Intelligence Scales (WIS), it has recently been argued that intelligence is underestimated in autism. This study examined RPM and WIS IQs in 48 individuals with autism, a mixed clinical (n = 28) and a neurotypical (n = 25) control group. Average RPM IQ was…

Lynn, Harvey and Nyborg [Lynn, R., Harvey, J., & Nyborg, H. (in press). Average intelligence predicts atheism rates across 137 nations. "Doi:10.1016/j.intell.2008.03.004".] discovered that average intelligence (IQ) co-varies with national atheism rates. Extending this work, we investigated relationships among individual IQ scores,…

This study investigated the Wechsler Performance IQ (PIQ) or Perceptual Reasoning Index (PRI)/ Perceptual Organization Index (POI) change over time and its relation to ability levels. PIQ or PRI/ POI was analyzed because of the known sensitivity of nonverbal scales to the Flynn effect. Scores were analyzed using two methods. First, analysis of…

Measurement invariance with respect to groups is an essential aspect of the fair use of scores of intelligence tests and other psychological measurements. It is widely believed that equal factor loadings are sufficient to establish measurement invariance in confirmatory factor analysis. Here, it is shown why establishing measurement invariance…

The assessment of cognitive ability in students with the most severe disabilities presents a challenge to the clinicians who are charged with this task. This article is the second of a two-part series that summarizes what is currently known about effective assessment of the cognitive ability of students with significant impairments in order to…

We followed up 67 children with autistic disorder (AD) and 31 children with pervasive developmental disorder not otherwise specified (PDDNOS) for more than 10 years by reviewing medical records at a clinic for children with developmental disabilities. The participants' data were collected between their first visit to the clinic and the visit at…

This study compared two popular measures of cognitive ability for preschool children. The "Wechsler Preschool and Primary Scale of Intelligence-Third Edition" (WPPSI-III) and the "Stanford-Binet Intelligence Scale-Fifth Edition" (SB5) were administered in a counterbalanced order to 36 typically developing 4-year-old children.…

This article presents results from two studies that included ethnically and socioeconomically diverse samples totaling 4,462 children in kindergarten through third grade. Each study examined the psychometric properties of a web-based, self-administered battery of assessments of socialemotional comprehension called "SELweb." Assessment…

At a time when, in most countries, the profession of school psychology is experiencing a period of growth and expansion, many problems still remain. The origins of these problems are linked to the historical development of the profession which has provided school psychologists with a unique and distinctive role in administering IQ tests and using…

In his comment on our literature review of data on the performance of sub-Saharan Africans on Raven's Progressive Matrices, Lynn (this issue) criticized our selection of samples of primary and secondary school students. On the basis of the samples he deemed representative, Lynn concluded that the average IQ of sub-Saharan Africans stands at 67…

This study examines the effect of parental education levels (PELs) on the fluid intelligence of Filipino public school students. The data were drawn from a normative study of a nonverbal intelligence test involving more than 2,700 students sampled across the country. As expected, PELs have a significant impact on fluid intelligence as measured…

In the first article of this special issue of the "Journal of Psychoeducational Assessment", I critiqued Flynn's theoretical explanation of the Flynn effect because he depended too heavily on an apparently huge generational gain on the WISC Similarities subtest; I claimed he was comparing apples with oranges because that subtest changed too much…

Linking country-level educational achievement with other country-level indicators has the potential to drive systemic educational changes, as these correlates may reflect characteristics relevant for policy-making decisions to improve educational effectiveness. This study establishes a nomological network of educational achievement at the country…