  We analyze 5 years of student records at the University of Oregon to estimate
the probability of success (as defined by superior undergraduate record;
sufficient for admission to graduate school) in Physics and Mathematics as a
function of SAT-M score. We find evidence of a nonlinear threshold: below SAT-M
score of roughly 600, the probability of success is very low. Interestingly, no
similar threshold exists in other majors, such as Sociology, History, English
or Biology, whether on SAT combined, SAT-R or SAT-M. Our findings have
significant implications for the demographic makeup of graduate populations in
mathematically intensive subjects, given the current distribution of SAT-M
scores.
