Investigating the ‘g’-saturation of various stratum-two factors using automatic item generation

Even though researchers agree on the hierarchical structure of intelligence there is considerable disagreement on the g-saturation of the lower stratum-two factors. In this article it is argued that the mixed evidence in the research literature can be at least partially attributed to the construct representation of the individual tests used to measure the stratum-two factors. In the study described here two top-down approaches to automatic item generation were used to build construct representation directly into the items. This enabled a clearer substantive interpretation of the shared commonalities extracted by the various stratum-two factors and helped to rule out alternative, but mathematically equivalent, structural models based on independent empirical evidence. This approach was used to investigate the g-saturation of five stratum-two factors using a sample of 240 male and female respondents. The results support the assumption that fluid intelligence exhibits the highest g-saturation.