President Eisgruber ’83’s 2018 Commencement address (President’s Page, July 11) fails to address or even mention the central source of doubt about the value of a college degree: selection bias. Undoubtedly college graduates earn more, on average, than non-graduates. But they are not otherwise a representative cross-section of their entire age cohort. They are the strivers and achievers of their cohort before they ever get to college. In fact, that is the basis on which they were selected for acceptance into college in the first place. It seems likely that they would out-earn those that were not selected, even if they never set foot thereafter in a college classroom at all.

I’m not convinced that the substantive content of college courses (other than in the STEM fields) adds much value to or for the graduate. The real value of a college degree is that it suggests that the graduate has the stamina and ability to run and survive the gauntlet. College is just an additional selection mechanism.