There is clearly something different about the physics and math GPA vs SAT distributions compared to all of the other majors we looked at . . . . In the other majors (history, sociology, etc.) it appears that hard work can compensate for low SAT score. But that is not the case in math and physics.
An SAT-M score below 600 almost insures a cumulative GPA of below 3.5 in math and physics. An SAT-M score above 670 almost insures a cumulative GPA of 3.5 or more in math and physics.
The investigators suggest that this supports the possibility that there are cognitive thresholds in physics and mathematics. But, their finding that "the probability of doing well in any particular quarter of introductory physics may be linear with SAT-M, but the probability of having a high cumulative GPA in physics or math is very non-linear in SAT-M," suggests a simpler alternative: physics and mathematics are cumulative, while most other college disciplines are less cumulative.
The study is based on five years of University of Oregon data. Other conclusions by the same researchers with the same data include:
1. SATs predict upper GPA with correlations in the 0.35 -- 0.50
2. Overachievers exist in most majors, with low SAT scores but
very high GPAs. These overachievers are disproportionately female.
3. Underachievers exist in all majors, with high SAT scores but
very low GPAs. These underachievers are disproportionately male.
The overachiever/underachiever disconnect is suggestive of a possible ADHD effect, as its manifestation is sex linked and captures many of the factors that figure into grades that are not captured in an SAT score.