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@AJCalhoun:
You write:
I notice someone stated that the average IQ in the US is 100 and extrapolated from this unscientific statistic (which is commonly believed but utterly proof proof),
erm... The average IQ is defined to be 100 in modern IQ measurement. Look it up: http://en.wikipedia.org/wiki/IQ
that it meant half the populace (even the part which has never taken an IQ test) has an IQ below 100. An average, brothers and sisters, is the aggregate number associated with any trait, divided by the number of subjects involved.
Yep. That's exactly what the mean is too. There are three commonly used statistical measures of the centre of a distribution: mean, mode, and median. The mean is identical to the average: the sum of the observations divided by the number of observations. The mode is the most common observation. The median is the observation below which half the observations fall.
It is only an average. Were the mean IQ of US citizens 100, then half would be below and half above. The average means almost nothing, since a handful of geniuses could skew it up to 100 and damn near all the rest of us could be virtually brain dead (which appears to be the case).
You are thinking of the median, not the mean, in what you write above. The skew could be important if IQ were measured the way you apparently think it is, but in fact it is defined to be a projection onto a Gaussian distribution with mean 100. A Gaussian is unimodal and symmetrical, so the mean, median, and mode are equal. 50% of the population is below the average by construction.
