Spearman's hypothesis tested comparing Korean young adults with various other groups of young adults on the items of the Advanced Progressive Matrices

Spearman's hypothesis tested at the subtest level of an IQ battery states that differences between races on the subtests of an IQ battery are a function of the g loadings of these subtests, such that there are small differences between races on subtests with low g loadings and large differences between races on subtests with high g loadings. Jensen (1998) stated that Spearman's hypothesis is a law-like phenomenon. It has also been confirmed many times at the level of items of the Raven's Progressive Matrices. This study hypothesizes that with concern to Spearman's hypothesis, subtests and items function in fundamentally the same way, and tested whether Spearman's hypothesis is confirmed at the item level for White-East Asian comparisons. A group of Korean young adults (N=205) was compared with other groups of young adults from Canada, the US, Russia, Peru and South Africa (total N=4770) who took the Advanced Progressive Matrices. Spearman's hypothesis was strongly confirmed with a sample-size-weighted r with a value of 0.63. Computing the g loadings of the items of the Raven with either the Raven-g or the Wechsler-g led to the same conclusions. Tests of Spearman's hypothesis yielded less-strong outcomes when the 36-item Advanced Progressive Matrices were used than when the 60-item Standard Progressive Matrices were used. There is a substantial correlation between sample size and the outcome of Spearman's hypothesis. So, all four hypotheses were confirmed, showing that a part of the subtest-level nomological net replicates at the item level, strengthening the position that, with concern to Spearman's hypothesis, subtests and items function fundamentally the same. It is concluded that Spearman's hypothesis is still a law-like phenomenon. Detailed suggestions for follow-up research are made.

SPEARMAN'S HYPOTHESIS TESTED COMPARING SAUDI ARABIAN CHILDREN AND ADOLESCENTS WITH VARIOUS OTHER GROUPS OF CHILDREN AND ADOLESCENTS ON THE ITEMS OF THE STANDARD PROGRESSIVE MATRICES

Spearman's hypothesis tested at the level of items states that differences between ethnic groups on the items of an IQ test are a function of the g loadings of these items, such that there are small differences between ethnic groups on items with low g loadings and large differences between ethnic groups on items with high g loadings; this has been confirmed in a limited number of studies. In this paper, Spearman's hypothesis was tested, comparing a group of Saudi children and adolescents (N=3209) with other groups of children and adolescents from Denmark, Cyprus, Croatia, Bosnia, South Africa, Estonia, Ukraine, Ireland, Russia and Chile (total N=9333). The analyses were carried out on twelve comparisons between the Saudi Arabian children and the other children. Spearman's hypothesis was confirmed less strongly than in other large-scale studies with a mean weighted r value of 0.44. The relevance of these findings for the discussion on the causes of group differences is discussed.

The importance of measurement invariance in neurocognitive ability testing

OBJECTIVE

Neurocognitive test batteries such as recent editions of the Wechsler's Adult Intelligence Scale (WAIS-III/WAIS-IV) typically use nation-level population-based norms. The question is whether these batteries function in the same manner across different subgroups based on gender, age, educational background, socioeconomic status, ethnicity, mother tongue, or race. Here, the author argues that measurement invariance is a core issue in determining whether population-based norms are valid for different subgroups.

METHOD

The author introduces measurement invariance, argues why it is an important topic of study, discusses why invariance might fail in cognitive ability testing, and reviews a dozen studies of invariance of commonly used neurocognitive test batteries.

RESULTS

In over half of the reviewed studies, IQ batteries were not found to be measurement invariant across groups based on ethnicity, gender, educational background, cohort, or age. Apart from age and cohort, test manuals do not take such lack of invariance into account in computing full-scale IQ scores or normed domain scores.

CONCLUSIONS

Measurement invariance is crucial for valid use of neurocognitive tests in clinical, educational, and professional practice. The appropriateness of population-based norms to particular subgroups should depend also on whether measurement invariance holds with respect to important subgroups.

Future Cognitive Ability: US IQ Prediction until 2060 Based on NAEP

The US National Assessment of Educational Progress (NAEP) measures cognitive competences in reading and mathematics of US students (last 2012 survey N = 50,000). The long-term development based on results from 1971 to 2012 allows a prediction of future cognitive trends. For predicting US averages also demographic trends have to be considered. The largest groups' (White) average of 1978/80 was set at M = 100 and SD = 15 and was used as a benchmark. Based on two past NAEP development periods for 17-year-old students, 1978/80 to 2012 (more optimistic) and 1992 to 2012 (more pessimistic), and demographic projections from the US Census Bureau, cognitive trends until 2060 for the entire age cohort and ethnic groups were estimated. Estimated population averages for 2060 are 103 (optimistic) or 102 (pessimistic). The average rise per decade is dec = 0.76 or 0.45 IQ points. White-Black and White-Hispanic gaps are declining by half, Asian-White gaps treble. The catch-up of minorities (their faster ability growth) contributes around 2 IQ to the general rise of 3 IQ; however, their larger demographic increase reduces the general rise at about the similar amount (-1.4 IQ). Because minorities with faster ability growth also rise in their population proportion the interactive term is positive (around 1 IQ). Consequences for economic and societal development are discussed.

Die Einflüsse des Migrationshintergrundes und psychischer Störungen auf kognitive Leistungsdaten einer SPZ-Inanspruchnahmepopulation

Zusammenfassung. Ein oft replizierter Befund ist, dass Kinder mit Migrationshintergrund schwächere Ergebnisse in Intelligenztests erzielen. Kognitive Leistungsmerkmale von Kindern mit F-Diagnosen gemäß ICD-10 wurden ebenfalls umfassend untersucht. Dennoch findet sich keine Studie, die explizit die Faktoren Störungsbild sowie Migrationshintergrund hinsichtlich kognitiver Leistungsdaten zueinander in Bezug setzt. Die vorliegende Studie untersucht im Rahmen eines allgemeinen linearen Modells den Einfluss des Faktors Migrationshintergrund sowie den gemeinsamen Einfluss mit der Variable psychische Störungen auf kognitive Leistungsdaten (Kaufman-Assessment Battery for Children [K-ABC], Melchers & Preuß, 2009 ). Zugrunde liegt eine SPZ-Stichprobe von 526 Vorschul- und Schulkindern einschließlich 238 Kindern mit Migrationshintergrund. Die meisten der Kinder weisen umschriebene Entwicklungsstörungen oder Verhaltensstörungen gemäß ICD-10 auf. Es konnten signifikante Haupteffekte für den Faktor Migrationshintergrund belegt werden, allerdings keine Interaktion mit dem Faktor Störungsbild. Die Ergebnisse unterstreichen den hohen Stellenwert vor allem des Migrationshintergrundes für die Erklärung kognitiver Leistungsdefizite.

International Perspectives on the Legal Environment for Selection

Perspectives from 22 countries on aspects of the legal environment for selection are presented in this article. Issues addressed include (a) whether there are racial/ethnic/religious subgroups viewed as “disadvantaged,” (b) whether research documents mean differences between groups on individual difference measures relevant to job performance, (c) whether there are laws prohibiting discrimination against specific groups, (d) the evidence required to make and refute a claim of discrimination, (e) the consequences of violation of the laws, (f) whether particular selection methods are limited or banned, (g) whether preferential treatment of members of disadvantaged groups is permitted, and (h) whether the practice of industrial and organizational psychology has been affected by the legal environment.

THE COGNITIVE COMPETENCES OF IMMIGRANT AND NATIVE STUDENTS ACROSS THE WORLD: AN ANALYSIS OF GAPS, POSSIBLE CAUSES AND IMPACT

Immigration, immigration policies and education of immigrants alter competence levels. This study analysed their effects using PISA, TIMSS and PIRLS data (1995 to 2012, N=93 nations) for natives' and immigrants' competences, competence gaps and their population proportions. The mean gap is equivalent to 4.71 IQ points. There are large differences across countries in these gaps ranging from around +12 to -10 IQ points. Migrants' proportions grow roughly 4% per decade. The largest immigrant-based 'brain gains' are observed for Arabian oil-based economies, and the largest 'brain losses' for Central Europe. Regarding causes of native-immigrant gaps, language problems do not seem to explain them. However, English-speaking countries show an advantage. Acculturation within one generation and intermarriage usually reduce native-immigrant gaps (≅1 IQ point). National educational quality reduces gaps, especially school enrolment at a young age, the use of tests and school autonomy. A one standard deviation increase in school quality represents a closing of around 1 IQ point in the native-immigrant gap. A new Greenwich IQ estimation based on UK natives' cognitive ability mean is recommended. An analysis of the first adult OECD study PIAAC revealed that larger proportions of immigrants among adults reduce average competence levels and positive Flynn effects. The effects on economic development and suggestions for immigration and educational policy are discussed.

A comparative study of general intelligence in Spanish and Moroccan samples

The aim of this study is to fill a gap in intelligence research by presenting data for the average IQ in Morocco and for a comparable sample in Spain. Adult samples were administered the Raven Standard Progressive Matrices (SPM) (Raven, Court, & Raven, 2001) and scored for the total test and for the three sub-factors of gestalt continuation, verbal-analytical reasoning and visuospatial ability identified by Lynn, Allik, and Irwing (2004). The total test and the three factors have shown satisfactory reliability. Our results for the Moroccan sample show significant relationship between general intelligence factor, gestalt continuation and visuospatial ability with education level and income. Conversely, these variables have been shown to be independent for the Spanish sample. This sample obtained significantly higher scores for the four factors assessed than the Moroccan one. These differences have been found also comparing samples with the same education levels. Finally, the errors percentage for Moroccans has been higher than for Spaniards in all the items, suggesting that the level of difficulty was higher for the Moroccan sample.

Exploring the Flynn effect in mentally retarded adults by using a nonverbal intelligence test for children

Increases in the scores on IQ tests across generations have been called the Flynn effect (FE). One of the unresolved questions is whether the FE affects all subsamples of the intellectual ability distribution equally. The present study was aimed at determining the size of the FE in moderately mentally retarded individuals. A nonverbal intelligence test developed for children, the Snijders-Oomen Nonverbal Intelligence Test (SON), was administered to 32 retarded adults with a mental age of 3-6 years. Sixty-nine children with a biological age in the same range and with normal intelligence served as a comparison group. Both an older and a more recent version of the SON were presented to all participants in a counterbalanced order. The proportion of items answered correctly was taken as a measure of the dependent variable. It was found that a FE existed in both the group of children and in the group of retarded adults, but that the FE was largest in the latter group. The importance of not using obsolete test norms when diagnosing mental retardation was stressed, and possible causes of the Flynn effect were discussed.

Educational Policy and Country Outcomes in International Cognitive Competence Studies

Prior studies of studentsqqaposxx and adultsqqaposxx cognitive competence have shown large differences between nations, equivalent to a difference of 5 to 10 years of schooling. These differences seem to be relevant because studies using different research paradigms have demonstrated that population-level cognitive abilities are related to a number of important societal outcomes, including productivity, democratization, and health. In this overview of transnational differences, we document a number of positive predictors of international differences in student competence, including the amount of preschool education, student discipline, quantity of education, attendance at additional schools, early tracking, the use of centralized exams and high-stakes tests, and adult educational attainment. We found rather negative relationships for grade retention rates, age of school onset, and class size. Altogether, these results, when combined with the outcomes of earlier studies, demonstrate that international differences in cognitive competence can be explained in part by aspects of the respective countriesqqaposxx educational systems and that these differences consequently can be reduced by reform of their educational policy. This has important implications not just for closing gaps in educational achievement, but for narrowing international gaps in wealth, health, and democracy.