Below are my scores on the WISC-R at age 12:

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Even though there were 12  subtests (2 of them optional: Span of attention & Visual planning) a hierarchical factor analysis of older Wechsler scales identified three major types of intelligence of  (verbal, spatial, and memory), and a single general factor (g) at the top of the hierarchy.

 

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An example of a hierarchal factor analysis of mental tests (though not actually from the Wechsler)

 

So even though Wechsler subjectively divided the tests into verbal and performance scales, factor analysis gave a more objective answer.

The same logic applies to race: Even though we can look at say 12 different “populations”: East Asians, Ashkenazi Jews, Whites, Middle Easterners, South Asians, Arctic people, Andaman Islanders, Southeast Asians, Pacific Islanders, Australoids, Congoids, Capoids, a hierarchal factor analysis of genomic phenotypes might identify three major factors “Negroid, Caucasoid and Mongolid” each of which could be divided into sub-factors.

There would also be a strong g factor at the top of the hierarchy, because we’re all human.

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