## Standard deviation of total SAT scores: not simply the sum of the standard deviations of subtests

Someone on Reddit for SlateStarCodex: AFAIK, SATs are normed to mean of 500 per section and standard deviation of 100. Assuming that math and verbal are highly correlated, that approximates to 1000 mean and 200 standard deviation for the SAT 1600 scale. The median reported score score was 1490, and even the 10th percentile was […]