The second-best predictors of performance are tests of general cognitive ability (26 percent). In contrast to case interviews and brainteasers, these are actual tests with defined right and wrong answers, similar to what you might find on an IQ test. They are predictive because general cognitive ability includes the capacity to learn, and the combination of raw intelligence and learning ability will make most people successful in most jobs. The problem, however, is that most standardized tests of this type discriminate against non-white, non-male test takers (at least in the United States).
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