Ideally your achieved IQ score is really a measure of your position within a normal distribution of IQ scores of your age group, where the mean (or peak) is standardized as 100 and one standard deviation equals 15 points. So an IQ of 130 is two Standard deviations above the mean and only ~ 2% of the people in your age group would be considered smarter than you.
I’m not sure age related decline factors into the decline of his IQ scores at all. That Hypothesis would only be true if the IQ-test he took was actually quite accurate and well-constructed, which would literally mean that in ~1955 only 0.05% of children in his age group were more intelligent than him and now something like 20% of ~65 year olds are more intelligent than him. Considering the stability of IQ it just doesn’t seem very plausible, that age-related decline would have hit him much harder than the average old person.
The article I quoted offered an explanation that I find much more plausible. It’s primary point wasn’t that this is the doing of the Flynn-effect, but the following:
“When too many children are found in the upper ranges, the scores are adjusted to fit the theoretical curve.This swells the number of scores in the 120-130 range and depresses the IQ scores of the entire gifted population. The attempt to artificially force the distribution of giftedness into the normal curve results in the disappearance of 1 1⁄2 standard deviations of intelligence. With today’s measuring devices, all IQ scores in the gifted range are most likely underestimates of ability.”
Ideally your achieved IQ score is really a measure of your position within a normal distribution of IQ scores of your age group, where the mean (or peak) is standardized as 100 and one standard deviation equals 15 points. So an IQ of 130 is two Standard deviations above the mean and only ~ 2% of the people in your age group would be considered smarter than you.
I’m not sure age related decline factors into the decline of his IQ scores at all. That Hypothesis would only be true if the IQ-test he took was actually quite accurate and well-constructed, which would literally mean that in ~1955 only 0.05% of children in his age group were more intelligent than him and now something like 20% of ~65 year olds are more intelligent than him. Considering the stability of IQ it just doesn’t seem very plausible, that age-related decline would have hit him much harder than the average old person.
The article I quoted offered an explanation that I find much more plausible. It’s primary point wasn’t that this is the doing of the Flynn-effect, but the following:
“When too many children are found in the upper ranges, the scores are adjusted to fit the theoretical curve.This swells the number of scores in the 120-130 range and depresses the IQ scores of the entire gifted population. The attempt to artificially force the distribution of giftedness into the normal curve results in the disappearance of 1 1⁄2 standard deviations of intelligence. With today’s measuring devices, all IQ scores in the gifted range are most likely underestimates of ability.”