Interesting, but at places with holistic admissions, esp. at LACs, the stats analysis only goes so far.
I think that above certain test scores – I dunno, maybe around 1450/32+ (isn’t a 32 about 95 percentile nationally?) and a certain GPA, at most highly selective colleges AOs turn to other determinants for admissions decisions: rigor, ECs, leadership, recommendations, essays, even character sometimes. My point is that getting 20 points on SAT or 1 point higher ACT is not the driving factor after you reach a test score/GPA threshold. On the back end they end up reporting the distribution of admitted scores, of course, which will fall across a range. But I don’t think there’s a direct line such that, for example, every 10 points increase in SAT gives you x percent increase in admissions chance. Admissions is not that linear.
Of course, I’m thinking of it from an individual applicant’s perspective and you’re analyzing aggregate data – but results of this analysis puts test scores in admissions driver’s seat more than appropriate and is not truly a measure of selectivity, IMHO.