Differentiation of Cognitive Abilities as a Function of Level of General Intelligence: A Latent Variable Approach

Abstract

Differentiation of cognitive abilities at different levels of general ability in same-aged subjects was tested by a latent variable approach in a multiple-groups design. Eighteen-year old conscripts (n = 14,720) representing the whole range of general ability in the male population, except for the mentally retarded, were tested by the Swedish Enlistment Battery. The sample of subjects was divided into 8, 16 and 32 groups according to level of general ability (G), and the amount of variance due to the ability factors Crystallized intelligence (Gc) and General visualization (Gv) was studied over the G levels. Variance contributed by Gc and Gv increased as the level of G increased. This effect was, however, not observed up through the highest levels of G, probably due to deficiencies in the measurement properties of the Gc and Gv tests at the highest G levels. Theoretical and methodological implications of the results are discussed, as are the consequences for the assessment of specific cognitive abilities at different levels of general ability.

Does age moderate the effect of IQ on the differentiation of cognitive abilities during childhood?

“…The inverse relationship between IQ and strength of subtest correlations has been confirmed many times during the last fifteen years (e.g., Abad, Colom, JuanEspinosa, & García, 2003;Carlstedt, 2001;Detterman, 1993;Detterman & Daniel, 1989;Evans, 1999;Facon, 2002Facon, , 2003aHunt, 1997;Jensen, 2003;Legree, Pifer, & Grafton, 1996;Lynn, 1990), and it is now considered practically a fact that remains only to be explained. Some studies (e.g., Fogarty & Stankov, 1995;Hartmann & Teasdale, 2004;Nesselroade & Thompson, 1995) have also given less support to the inverse relationship, and these also require an explanation.…”

Spearman's “Law of Diminishing Returns” tested with two methods

“…When consulting the literature the majority of studies support SLODR (ability) (e.g., Abad, Colom, Juan-Espinosa, & Garcia, 2003;Baumeister & Bartlett, 1962;Birren, 1952;Carlstedt, 2001;Coyle, 2002;Deary et al, 1996;Der & Deary, 2002;Detterman & Daniels, 1989;Detterman et al, 1992;Evans, 1999;Filella, 1960;Jäger, 1964;Jäger & Todt, 1964;Jensen, 2003;Kane, 2000;Legree, Pifer, & Grafton, 1996;Lienert, 1961Lienert, , 1964Lienert & Faber, 1963;Lynn, 1992;Lynn & Cooper, 1993, 1994Mitchell, 1956;Maxwell, 1972;Nesselroade & Thompson, 1995;Reinert, Baltes, & Schmidt, 1965;Segel, 1948;Spearman, 1927;Wewetzer, 1958) but some studies either find no difference in g saturation or find the opposite pattern (Amelang & Langer, 1968;Bloom et al, 1988;DeVoss, 1926;Eyferth, 1963;Facon, 2004;Fogarty & Stankov, 1995;Hartmann & Teasdale, 2004, accepted for publication; Roesslein, 1953). However, not all studies are equally valid and it is therefore necessary to look at the individual studies in order to investigate whether the specific study controls for potential confounders.…”

Differentiation of cognitive abilities as a function of neuroticism level: A measurement equivalence/invariance analysis

“…Two of the more well-known differentiation hypotheses are the cognitive-differentiation hypothesis and the age-differentiation hypothesis. The cognitive-differentiation hypothesis posits that abilities become increasingly distinct at higher levels of general intelligence (e.g., Carlstedt, 2000;Detterman & Daniel, 1989, see also Spearman, 1927). For example, Abdad, Colom, Juan-Espinosa, and García, (2003) recently demonstrated that the g factor accounts for more variance among less able individuals than it does among more able individuals, and that the average correlation among ability tests is greater for low ability individuals than it is for high ability individuals.…”