Developmental predictors of children's fraction concepts and procedures at the end of fourth grade were investigated in a 2-year longitudinal study. Participants were 357 children who started the study in third grade. Attentive behavior, language, nonverbal reasoning, number line estimation, calculation fluency, and reading fluency each…

This study compares Spanish morphosyntax error types and magnitude in monolingual Spanish and Spanish-English bilingual children with typical language development (TD) and language impairment (LI). Performance across groups was compared using cloze tasks that targeted articles, clitics, subjunctives, and derivational morphemes in 57 children.…

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…

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…

The acknowledged high relationship between working memory and intelligence suggests common underlying cognitive mechanisms and, perhaps, shared biological substrates. If this is the case, improvement in working memory by repeated exposure to challenging span tasks might be reflected in increased intelligence scores. Here we report a study in which…

Low scores across a battery of tests are common in healthy people and vary by demographic characteristics. The purpose of the present article was to present the base rates of low scores for the Wechsler Intelligence Scale for Children, fourth edition (WISC-IV; D. Wechsler, 2003). Participants included 2,200 children and adolescents between 6 and…

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…

This register-based longitudinal study of 392 969 Norwegians examined associations between birth order, gender and educational attainment at age 25 years within families (fixed effects regression) and between families (ordinary OLS regression). Data were retrieved from national registers for births of mothers with single births only and a first…

Item responses to Digit Span and Letter-Number Sequencing were analyzed to develop a better-refined model of the two working memory tasks using the finite mixture (FM) modeling method. Models with ordinal latent traits were found to better account for the independent sources of the variability in the tasks than those with continuous traits, and…

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.…

The Kaufman Adolescent and Adult Intelligence Test (KAIT[TM]) is an individually administered test of intelligence for individuals ranging in age from 11 to 85+ years. The item response theory-likelihood ratio procedure, based on the two-parameter logistic model, was used to detect differential item functioning (DIF) in the KAIT across males and…

The analysis of response inconsistency is a crucial aspect of intellectual and clinical psychological assessment. Erratic patterns of failures and successes across and within particular domains qualify the measurement of intellectual potential and functioning. Although the interpretation of intertest scatter (inconsistencies between subtest…

Instructions for the Matrix Reasoning Test (MRT) of the Wechsler Adult Intelligence Scale-Third Edition were modified by explicitly stating that the subtest was untimed or that a per-item time limit would be imposed. The MRT was administered within one of four conditions: with (a) standard administration instructions, (b) explicit instructions…