Johan Olav Undheim

The Hierarchical Organization of Cognitive Abilities: Restoring General Intelligence Through the Use of Linear Structural Relations (LISREL).

While considerable support has been obtained for the distinction, due to Cattell and Horn, between the broad factors fluid intelligence (Gf) and crystallized intelligence (Gc), there is also some evidence that Gf is equivalent to the factor of general intelligence (g). This hypothesis is investigated by using LISREL to specify higher-order models in reanalyses of three sets of psychometric data from subjects 11, 13, and 15 years old, respectively. The three studies unanimously showed Gf to be equivalent with a general factor. The discussion is centered upon the use of LISREL and the differences in results between the exploratory and confirmatory approaches to factor analysis.

Stability and Change in Broad and Narrow Factors of Intelligence from Ages 12 to 15 Years.

A battery of cognitive tests was administered in the 6th grade (12-year-olds) and again in 9th grade (15-year-olds) to a sample of 225 boys and 242 girls. In the 8th grade, the same students answered an inventory about reading activities. Hierarchical confirmatory factor models were fitted to the test data from each of the 2 occasions, defining a General Intelligence factor and residual factors representing Crystallized Intelligence and General Visualization. Results indicate high stability for the general factor (.92 to .94) and for the residual of the General Visualization factor

Socio‐economic Factors and Sex Differences in an Egalitarian Educational System: academic achievement in 16‐year‐old Norwegian students

ABSTRACT The importance of socio‐economic factors and sex differences in an educational system characterized by mainstreaming, no ability grouping within classes, very little acceleration, and no holdbacks of students was studied. Cohort data of 16‐year‐olds from the township of Trondheim (N = 1750) and a sample of about 250 students were analyzed, using graduate records, questionnaires and inventories. Sex differences in average achievements were small, over‐all about 0.4 SD in favour of girls for Norwegian (mother language) and about 0.1 SD in favour of boys for mathematics. However, the proportion of boys who obtained the highest grade in mathematics was larger than expected from the mean difference in the subjects. Parent education was a powerful predictor of student achievement. Questionnaire data showed that sex‐stereotypes were strong regarding abilities and career aspirations. The analysis suggested several ways in which sex and socio‐economic differences in achievements may be mediated in an egal...

Critical evaluation of Guilford's structure-of-intellect theory

Abstract The structure-of-intellect (SI) theory is evaluated within a framework of considerations of capitalization on chance. This empirical problem is placed in a larger perspective of concern for the general conceptual value of the theory in the study of human intelligence. The factor analytic support for the theory is found to be lacking in several notable respects. At best the research intended to support the model must be considered exploratory. But the model has provided a useful scheme for test construction and for indicating interesting hypotheses about qualities of intellect. Even in this context, however, there are several problems with the theory. The theory provides only a static taxonomy and thus affords very limited possibilities for understanding developmental issues.

Academic Achievements of High‐ability Students in Egalitarian Education: a study of able 16‐year‐old students in Norway

ABSTRACT Forty‐three high‐ability students were selected through tests of analytic ability at 10 and 12 years of age; school achievement data were collected when they graduated from middle school when they were 15‐16 years old, and in the same year they answered a general‐knowledge test and a questionnaire about their activities, attributions and self‐evaluations regarding past and future achievements. The ability data showed small sex differences. Nevertheless, the 23 boys did better in most academic subjects; in mathematics 3‐4 times as many boys as girls obtained top grades. Boys also excelled in general factual knowledge. Parents ‘ educational resources had a correlation of 0.60 with school achievement. Their academic achievements were related to the reported effort, work habits, attributions, and to the other self‐evaluations. However, the superiority of boys in mathematics was not adequately explained. The quite similar superiority of boys in general factual knowledge is seen as being contra‐indicat...

Dyslexia and hormone deficiences

From a group of 75 children, originally selected as dyslectic on the basis of their reading and/or spelling problems relative to a total group of 1000 4.th grade children in the city of Trondheim, blood tests were obtained on 35 children. A control group of 45 children was drawn among the 1000 children. Among the 12 different hormones measured, significant differences came out on cortisol, triiodothyronine (T. 3), prolactin, and human growth hormone (HGH, somatotrophin) in boys and girls separately. A follow-up study of 22 dyslectic children from the same cohort gave results consistent with those obtained in the original study. The higher values of the dyslectic group on cortisol and prolactin may suggest the dyslectics to be in a stressful situation, possibly due to their language problems in school. The most striking difference, however, was the very low levels of HGH in the dyslectic group—to the extent that there was little overlap in the two distributions. This result was totally unexpected and is, in fact, opposite of what to be expected on the basis of at least short — time stress events. The results holds up when age and pubery development are controlled for.RésuméOn a extrait parmi 1000 enfants de 10 ans de la ville de Trondheim un groupe de 75 enfants dyslexiques. 45 autres enfants appartenant à la même population ont servi de groupe-contrôle. Les comparaisons entre normaux et dyslexiques ont porté sur des mesures physiologiques hormonales.Une première étude faite à partir de 35 des enfants dyslexiques a permis de constater l’existence de différences significatives avec le groupe contrôle pour les hormones suivantes, chez les garçons comme chez les filles: cortisol (les corticoïdes), triiodothyronine (t.3.), prolactine et hormone de croissance (HGH, somatotrophine). Une seconde étude faite avec 22 autres enfants dyslexiques du même groupe a confirmé l’existence des mêmes différences.Les valeurs élevées pour le cortisol et la prolactine chez les dyslexiques suggèrent que ces sujects sont dans une situation de stress à cause de leurs problèmes de langage. Les différences les plus frappantes concernent cependant les valeurs très faibles d’H.G.H chez les dyslexiques avec très peu de recouvrement des distributions des deux groupes (dyslexiques et groupe contrôle). Ce résultat surprenant est contraire à ce qui était attendu par rapport aux phénomènes de stress de courte durée. Les résultats obtenus se maintiennent si l’on contrôle l’âge et l’apparition de la puberté.

Taking Stock of What There is: The Case of Cognitive Abilities

Publisher Summary This chapter discusses with the case of cognitive abilities. For a long time, individual difference research on cognitive or intellectual functions was almost synonymous with factor-analytic research. One may distinguish between two general approaches to the study of processes underlying individual differences in intelligence, the cognitive-correlates approach and the cognitive-components approach. In the first approach, the one initially opening up this area of research, subjects high and low on some traditional intellectual measures are tested on tasks that contemporary information-processing psychologists believe involve certain basic processing skills. Also, one should point out that an approach often considered to be separate of the process analytic endeavors, characterized by an emphasis on the biological basis of intelligence, has some of its roots in the cognitive correlates approach. In the second approach, the cognitive-components approach, the aim is to develop processing models of complex cognitive tasks, finding ways to de-compose the tasks into simpler components. The chapter also highlights the dependence on ability factors in processing studies.