Berkson’s Paradox

A kind of survivorship bias in that when there are two positively correlating traits that are (ostensibly) negatively correlated in a population that selects for these traits. For instance, GPA and SAT scores. Although it would seem at first glance that having a higher SAT score doesn’t lead to higher grades in a particular college, this leaves out the individuals with higher SAT scores that would have had higher GPAs had they not picked a another (better ranked) school to go to. Likewise, applicants with lower SAT scores that would have scored badly would not have been accepted to the school in the first place.