It always surprises me how some people are shocked a plot of P(student learned the class material well) is starkly different from P(student learned the class ma

It always surprises me how some people are shocked a plot of P(student learned the class material well) is starkly different from P(student learned the class material well | student was hard-working enough to secure admission through one of the most selective* processes). * Minus the legacies and the atheletic admissions I guess.