OP’s claim is that intelligence is positively skewed. Counter-points are “most brains are slightly worse” (Donald Hobson) and “you oversample the high-intelligence people, so your claim is biased because of availability” (Ericf).
Both of these counter-points agree with, rather than disagree with, lsusr’s point. Most brains are slightly worse implies positive skew and to the extent that lsusr oversamples high-intelligence people, they are underestimating how positively skewed intelligence is yet still conclude it is positively skewed (caveat: as Donald Hobson says, the measurement approach can be really important here, but for the sake of argument let’s say lsusr is talking about latent intelligence, and our measures just need to catch up with the theory).
Ericf also makes another interesting point- “variation in low intelligence is less identifiable than variation in high intelligence,” 160 vs. 130 IQ people will act differently, but 40 vs. 70 IQ people won’t so much, or at least the IQ test is better at delineating on the high end than low end. I am no expert on the measurement of intelligence, but this point probably shouldn’t just be taken at face value- for example, individuals with Down’s syndrome consistently have IQs less than 70 and getting below 70 is rare, as expected since IQ is designed to be Gaussian. But the implication of that is that as rare (and therefore difficult to dig into) as low IQs are, high IQs are...equally rare (and therefore difficult to dig into).
I agree that OP’s claim should also be subjected to scrutiny -simply saying intelligence is positively skewed doesn’t make it so- but I also don’t find the present set of counter-points either that contradictory or that convincing either. Just my two cents.
OP’s claim is that intelligence is positively skewed. Counter-points are “most brains are slightly worse” (Donald Hobson) and “you oversample the high-intelligence people, so your claim is biased because of availability” (Ericf).
Both of these counter-points agree with, rather than disagree with, lsusr’s point. Most brains are slightly worse implies positive skew and to the extent that lsusr oversamples high-intelligence people, they are underestimating how positively skewed intelligence is yet still conclude it is positively skewed (caveat: as Donald Hobson says, the measurement approach can be really important here, but for the sake of argument let’s say lsusr is talking about latent intelligence, and our measures just need to catch up with the theory).
Ericf also makes another interesting point- “variation in low intelligence is less identifiable than variation in high intelligence,” 160 vs. 130 IQ people will act differently, but 40 vs. 70 IQ people won’t so much, or at least the IQ test is better at delineating on the high end than low end. I am no expert on the measurement of intelligence, but this point probably shouldn’t just be taken at face value- for example, individuals with Down’s syndrome consistently have IQs less than 70 and getting below 70 is rare, as expected since IQ is designed to be Gaussian. But the implication of that is that as rare (and therefore difficult to dig into) as low IQs are, high IQs are...equally rare (and therefore difficult to dig into).
I agree that OP’s claim should also be subjected to scrutiny -simply saying intelligence is positively skewed doesn’t make it so- but I also don’t find the present set of counter-points either that contradictory or that convincing either. Just my two cents.