Measurement of Level I and Level II Mental Abilities as a Function of Test and Socioeconomic Status

In Jensen's dual process hypothesis of mental abilities Digit-Span and Progressive Matrices are seen as relatively pure measures of Level I and Level II, respectively, while paired-associate learning is seen as a less pure measure of Level I since it can vary with respect to loading on Level II ability. A sample of 227 10- to 11-yr.-old New Zealand children from varying socioeconomic groups completed Raven's Progressive Matrices, a digit-span test, and three paired-associate learning tests varying in abstractness. Analysis indicated no clear distinction between relatively pure and impure measures of Level I ability. Both Raven IQ and digit span were related to socioeconomic status, while paired-associate learning was not.