Multidimensional scaling vs. factor analysis of Wechsler's intelligence scales.

The relations between principal component and principal factor analysis, on the one hand, and metric and nonmetric multidimensional scaling, on the other, were explored by applying all four methods to the standardization data for the WAIS-R, the WISC-R, and the WPPSI. For each of the instruments, the first component/factor was a general one that had no counterpart in the two scaling dimensions. The second component/factor and the first scaling dimension differentiated the Verbal from the Performance subtests, whereas the third component/factor and the second scaling dimension appeared to represent what has been called Freedom from Distractibility. The tendency of multidimensional scaling to remove the first general component/factor may be an undesirable feature of that method for investigating structure in the area of human abilities.