Lecture 1: Factor-Analytic Investigations of Cognitive Abilities

Abstract

Much of what we know about intelligence and cognitive abilities derives from factor-analytic investigations using psychological tests, and occasionally, other kinds of observational data. The basic scientific questions motivating these studies have been: (a) what are the basic dimensions of cognitive abilities, and (b) what is the “structure” of these abilities, that is, in what way are they related, and can an understanding of this structure lead to a theory of intelligence and cognition? In the attempt to answer the first question, the responses have ranged all the way from Spearman’s (1927) initial proposal that there is only one basic cognitive ability, called “g”, to Guildford’s (1967) claim that there may be as many as 120 or more such abilities. To the outsider to the field, the multiplicity of answers seems overwhelming, puzzling and even suspect. Obviously, there is a need for clarity and resolution here.