> First, on a population level IQ is very stable with age. Over a study of 87,498 Scottish children, age 11 IQ and adult IQ correlated at 0.66 [1], about as str

> First, on a population level IQ is very stable with age. Over a study of 87,498 Scottish children, age 11 IQ and adult IQ correlated at 0.66 [1], about as strong and impressive a correlation as you’ll ever find in the social sciences. But “correlation of 0.66” is also known as “only predicts 44% of the variance”. On an individual level, it is totally possible and not even that surprising to have an IQ of 100 at age 11 but 120 at age 30, or vice versa. Any IQ score you got before high school should be considered a plausible prediction about your adult IQ and nothing more. Quoted from http://slatestarcodex.com/2017/09/27/against-individual-iq-worries/ http://slatestarcodex.com/2017/09/27/against-individual-iq-w... Ref [1] is https://www.huffingtonpost.com/scott-barry-kaufman/intelligence-is-still-not_b_1078112.html https://www.huffingtonpost.com/scott-barry-kaufman/intellige...