Human Growth and Development / Unit 7 HGD 0938 worked example, 60 to 90 seconds
The IQ Scale
The idea
Intelligence tests are normed so that each age group's mean is one hundred and the standard deviation is fifteen. About sixty-eight percent of people score between eighty-five and one hundred fifteen, within one standard deviation of the mean. A score of seventy lies two standard deviations below the mean and one hundred thirty two above; about two percent of people fall beyond each.
In practice
Two children scoring seventy and one hundred thirty, each two standard deviations from the mean, at opposite ends.
Where people slip
A good test needs reliability, giving consistent results, and validity, measuring what it claims to measure. A score of seventy or one hundred thirty is one marker, not a diagnosis: intellectual disability also requires limits in adaptive behaviour, and giftedness has no universal definition. A score is one piece of the picture.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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