Measuring success, chapters 2 and 3

Chapter 2 is a very detailed breakdown of data on college grades (freshman and 4-year) and college completion rates versus SAT score and high school GPA.  The message from many analyses is clear:  In every band of high school GPAs the SAT has real predictive power for performance in college, by multiple measures.

Of course, one cannot discuss this without discussing equity, so they make the same point as the previous chapter:  The SAT actually over-predicts college performance for minorities (because performance is also affected by disadvantages that are NOT fully captured in scores).  More importantly, they cite a different study than the previous chapter cited.  This gives me somewhat greater confidence about the point, when multiple investigators can cite a plethora of studies rather than everyone rallying around the same study.  We should always be suspicious of narratives built around This One Study.

Chapter 3 has one big point:  Grade inflation is real, and it's more prominent at schools serving affluent and white kids than schools serving poor kids from disadvantaged minority groups.  Consequently, if you base admissions decisions on grades rather than test scores you won't actually accomplish your equity goals.  Their main evidence for inflation is that they look at how high school grades have trended upward (in many but not all schools) for students in comparable bands of SAT scores.  Since the College Board does a lot of work to try to make SAT scores comparable across years, this strongly suggests that grading is getting more lenient (in some but not all schools).  And the schools at which grading is getting more lenient (based on this line of analysis) are whiter and more affluent than the schools with less grade inflation.

Not having examined the data myself, I am obviously not in a position to weigh in on the validity of this work, but if other authors have found similar things in multiple independent analyses then we should seriously consider the implications.