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IQ

intelligence quotient: a standard measure of an individual’s intelligence level based on psychological tests. In the early years of intelligence testing, IQ was calculated by dividing the mental age by the chronological age and multiplying by 100 to produce a ratio IQ. This concept has now mostly been replaced by the deviation IQ, computed as a function of the discrepancy of an individual score from the mean (or average) score. The mean IQ is customarily 100, with slightly more than two thirds of all scores falling within plus or minus 15 points of the mean (usually one standard deviation). More than 95% of all scores fall between 70 (two standard deviations below the mean) and 130 (two standard deviations above the mean). Some tests yield more specific IQ scores, such as a verbal IQ, which measures verbal intelligence, and a performance IQ, which measures nonverbal intelligence. Discrepancies between the two can be used diagnostically to detect learning disabilities or specific cognitive deficiencies. Additional data are often derived from IQ tests, such as performance speed, freedom from distractibility, verbal comprehension, and perceptual organization indices. There are critics who consider the concept of IQ (and other intelligence scales) to be flawed. They point out that the IQ test is more a measure of previously learned skills and knowledge than of underlying native ability and that many participants are simply not accustomed to sitting still and following orders (conditions that such tests require), although they function well in the real world. Critics also refer to cases of misrepresentation of facts in the history of IQ research. Nevertheless, these problems seem to apply to the interpretation of IQ scores rather than the validity of the scores themselves.

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Psychology term of the day

March 28th 2024

win–lose dynamic

win–lose dynamic

the conflict-promoting processes that occur in situations in which competitive reward structures cause participants to feel they can only succeed if others fail.