Ap psychology battle of the brains answers the idea of a single, overall intelligence is called

Called "g factor" or general intelligence.

The G factor is a concept developed to establish a measure, in psychometric research, of human intelligence. Part of the idea that you can determine the intelligence of individuals to compare them with people who have the same age, or the same educational level. Generally, the intelligence tests have a level of reliability, therefore they are only an estimate of the intelligence of the individuals.

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