Commenter blubbalubba writes:

When will you do another study on the post 2016 SAT? There was a 60 points inflation. It would be great if you looked into this recent change.

For years I’ve complained that the SAT is normed on college bound students, but in order to convert it to IQ equivalents, we need to know how the general U.S. population would score. Well perhaps someone from the college board was reading because their website has now started publishing two types of norms:

Nationally Representative Sample Percentiles are derived
from a research study of U.S. students in grades 11 and
12 and are weighted to represent all U.S. students in those
grades, regardless of whether they typically take the SAT.

SAT User Percentiles are based on the actual scores of
students in the past three graduating classes who took
the current SAT during high school. These user percentiles
are reported on tests completed in August 2019 through
June 2020.

So for example, a combined score (verbal + math) of 1055, which makes you dead average (50th percentile) among the college bound elite who takes the SAT, would make you slightly above average (59th percentile) among the nationally representative sample.

One problem is even the nationally representative sample is a bit elite because many of the dullest Americans don’t make it to grade 11, let alone grade 12. so how do we adjust for this?

It turns out we don’t have to because only 6% of U.S. high school students now dropout, and even assuming none of this 6% would score high, the percentiles would only change by a fraction of a percent. For example, if you score in the top 1 out of 100 high school seniors, including the high school dropouts would only move you to 1 out of 106. A trivial difference (at least at the high end)

Verbal SAT (Evidence-based reading & writing)

On this section the median high school senior scores 510 so let this = verbal IQ 100. The 98th percentile is 720 so let this = verbal IQ 130. Thus:

Verbal IQ = 27 + 0.14(verbal SAT)

Math SAT

On this section the median high school senior scores 505 and the top 2% score 740, so let these scores equate to math IQs of 100 and 130 respectively. Thus:

Math IQ = 36 + 0.13(math SAT)

Combined SAT (verbal + math)

Overall the median high school senior scores 1055 and the top 2% score 1480, so let these scores equate to composite IQs of 100 and 130 respectively. Thus:

IQ = 26 + 0.07(Combined SAT)

Is the SAT an IQ test?

I have never found a study correlating the SAT with Wechsler IQ in the general U.S. population but I did find such a study correlating the WIAT (which also measures reading and math knowledge) with IQ in a very representative sample of U.S. 16-19 year-olds (n = 142). Reading comprehension and math reasoning correlated 0.71 and 0.82 with Wechsler full-scale IQ respectively (WAIS-III WMS-III Technical Manual page 85-86).

However there are several reasons for thinking the SAT may correlate somewhat less: 1) the enormous importance of the test for some creates huge differences in motivation, test-prep and cheating, and 2) people diagnosed with learning disabilities can take the test without time limits, 3) my research on the Wechsler IQs of Ivy Leagues students suggest they regress at least a third of the way to the mean from their SAT scores, suggesting a correlation no higher than 0.66.